WorldWideScience

Sample records for human event analysis

  1. Human reliability analysis using event trees

    International Nuclear Information System (INIS)

    Heslinga, G.

    1983-01-01

    The shut-down procedure of a technologically complex installation as a nuclear power plant consists of a lot of human actions, some of which have to be performed several times. The procedure is regarded as a chain of modules of specific actions, some of which are analyzed separately. The analysis is carried out by making a Human Reliability Analysis event tree (HRA event tree) of each action, breaking down each action into small elementary steps. The application of event trees in human reliability analysis implies more difficulties than in the case of technical systems where event trees were mainly used until now. The most important reason is that the operator is able to recover a wrong performance; memory influences play a significant role. In this study these difficulties are dealt with theoretically. The following conclusions can be drawn: (1) in principle event trees may be used in human reliability analysis; (2) although in practice the operator will recover his fault partly, theoretically this can be described as starting the whole event tree again; (3) compact formulas have been derived, by which the probability of reaching a specific failure consequence on passing through the HRA event tree after several times of recovery is to be calculated. (orig.)

  2. Analysis for Human-related Events during the Overhaul

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Tae; Kim, Min Chull; Choi, Dong Won; Lee, Durk Hun [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2011-10-15

    The event frequency due to human error is decreasing among 20 operating Nuclear Power Plants (NPPs) excluding the NPP (Shin-Kori unit-1) in the commissioning stage since 2008. However, the events due to human error during an overhaul (O/H) occur annually (see Table I). An analysis for human-related events during the O/H was performed. Similar problems were identified for each event from the analysis and also, organizational and safety cultural factors were also identified

  3. Analysis of operational events by ATHEANA framework for human factor modelling

    International Nuclear Information System (INIS)

    Bedreaga, Luminita; Constntinescu, Cristina; Doca, Cezar; Guzun, Basarab

    2007-01-01

    In the area of human reliability assessment, the experts recognise the fact that the current methods have not represented correctly the role of human in prevention, initiating and mitigating the accidents in nuclear power plants. The nature of this deficiency appears because the current methods used in modelling of human factor have not taken into account the human performance and reliability such as it has been observed in the operational events. ATHEANA - A Technique for Human Error ANAlysis - is a new methodology for human analysis that has included the specific data of operational events and also psychological models for human behaviour. This method has included new elements such as the unsafe action and error mechanisms. In this paper we present the application of ATHEANA framework in the analysis of operational events that appeared in different nuclear power plants during 1979-2002. The analysis of operational events has consisted of: - identification of the unsafe actions; - including the unsafe actions into a category, omission ar commission; - establishing the type of error corresponding to the unsafe action: slip, lapse, mistake and circumvention; - establishing the influence of performance by shaping the factors and some corrective actions. (authors)

  4. Human performance analysis of industrial radiography radiation exposure events

    International Nuclear Information System (INIS)

    Reece, W.J.; Hill, S.G.

    1995-01-01

    A set of radiation overexposure event reports were reviewed as part of a program to examine human performance in industrial radiography for the US Nuclear Regulatory Commission. Incident records for a seven year period were retrieved from an event database. Ninety-five exposure events were initially categorized and sorted for further analysis. Descriptive models were applied to a subset of severe overexposure events. Modeling included: (1) operational sequence tables to outline the key human actions and interactions with equipment, (2) human reliability event trees, (3) an application of an information processing failures model, and (4) an extrapolated use of the error influences and effects diagram. Results of the modeling analyses provided insights into the industrial radiography task and suggested areas for further action and study to decrease overexposures

  5. Analysis of human error and organizational deficiency in events considering risk significance

    International Nuclear Information System (INIS)

    Lee, Yong Suk; Kim, Yoonik; Kim, Say Hyung; Kim, Chansoo; Chung, Chang Hyun; Jung, Won Dea

    2004-01-01

    In this study, we analyzed human and organizational deficiencies in the trip events of Korean nuclear power plants. K-HPES items were used in human error analysis, and the organizational factors by Jacobs and Haber were used for organizational deficiency analysis. We proposed the use of CCDP as a risk measure to consider risk information in prioritizing K-HPES items and organizational factors. Until now, the risk significance of events has not been considered in human error and organizational deficiency analysis. Considering the risk significance of events in the process of analysis is necessary for effective enhancement of nuclear power plant safety by focusing on causes of human error and organizational deficiencies that are associated with significant risk

  6. Human reliability analysis of dependent events

    International Nuclear Information System (INIS)

    Swain, A.D.; Guttmann, H.E.

    1977-01-01

    In the human reliability analysis in WASH-1400, the continuous variable of degree of interaction among human events was approximated by selecting four points on this continuum to represent the entire continuum. The four points selected were identified as zero coupling (i.e., zero dependence), complete coupling (i.e., complete dependence), and two intermediate points--loose coupling (a moderate level of dependence) and tight coupling (a high level of dependence). The paper expands the WASH-1400 treatment of common mode failure due to the interaction of human activities. Mathematical expressions for the above four levels of dependence are derived for parallel and series systems. The psychological meaning of each level of dependence is illustrated by examples, with probability tree diagrams to illustrate the use of conditional probabilities resulting from the interaction of human actions in nuclear power plant tasks

  7. Comparison of methods for dependency determination between human failure events within human reliability analysis

    International Nuclear Information System (INIS)

    Cepis, M.

    2007-01-01

    The Human Reliability Analysis (HRA) is a highly subjective evaluation of human performance, which is an input for probabilistic safety assessment, which deals with many parameters of high uncertainty. The objective of this paper is to show that subjectivism can have a large impact on human reliability results and consequently on probabilistic safety assessment results and applications. The objective is to identify the key features, which may decrease of subjectivity of human reliability analysis. Human reliability methods are compared with focus on dependency comparison between Institute Jozef Stefan - Human Reliability Analysis (IJS-HRA) and Standardized Plant Analysis Risk Human Reliability Analysis (SPAR-H). Results show large differences in the calculated human error probabilities for the same events within the same probabilistic safety assessment, which are the consequence of subjectivity. The subjectivity can be reduced by development of more detailed guidelines for human reliability analysis with many practical examples for all steps of the process of evaluation of human performance. (author)

  8. Comparison of Methods for Dependency Determination between Human Failure Events within Human Reliability Analysis

    International Nuclear Information System (INIS)

    Cepin, M.

    2008-01-01

    The human reliability analysis (HRA) is a highly subjective evaluation of human performance, which is an input for probabilistic safety assessment, which deals with many parameters of high uncertainty. The objective of this paper is to show that subjectivism can have a large impact on human reliability results and consequently on probabilistic safety assessment results and applications. The objective is to identify the key features, which may decrease subjectivity of human reliability analysis. Human reliability methods are compared with focus on dependency comparison between Institute Jozef Stefan human reliability analysis (IJS-HRA) and standardized plant analysis risk human reliability analysis (SPAR-H). Results show large differences in the calculated human error probabilities for the same events within the same probabilistic safety assessment, which are the consequence of subjectivity. The subjectivity can be reduced by development of more detailed guidelines for human reliability analysis with many practical examples for all steps of the process of evaluation of human performance

  9. Trend analysis of human error events and assessment of their proactive prevention measure at Rokkasho reprocessing plant

    International Nuclear Information System (INIS)

    Yamazaki, Satoru; Tanaka, Izumi; Wakabayashi, Toshio

    2012-01-01

    A trend analysis of human error events is important for preventing the recurrence of human error events. We propose a new method for identifying the common characteristics from results of trend analysis, such as the latent weakness of organization, and a management process for strategic error prevention. In this paper, we describe a trend analysis method for human error events that have been accumulated in the organization and the utilization of the results of trend analysis to prevent accidents proactively. Although the systematic analysis of human error events, the monitoring of their overall trend, and the utilization of the analyzed results have been examined for the plant operation, such information has never been utilized completely. Sharing information on human error events and analyzing their causes lead to the clarification of problems in the management and human factors. This new method was applied to the human error events that occurred in the Rokkasho reprocessing plant from 2010 October. Results revealed that the output of this method is effective in judging the error prevention plan and that the number of human error events is reduced to about 50% those observed in 2009 and 2010. (author)

  10. Human Performance Event Database

    International Nuclear Information System (INIS)

    Trager, E. A.

    1998-01-01

    The purpose of this paper is to describe several aspects of a Human Performance Event Database (HPED) that is being developed by the Nuclear Regulatory Commission. These include the background, the database structure and basis for the structure, the process for coding and entering event records, the results of preliminary analyses of information in the database, and plans for the future. In 1992, the Office for Analysis and Evaluation of Operational Data (AEOD) within the NRC decided to develop a database for information on human performance during operating events. The database was needed to help classify and categorize the information to help feedback operating experience information to licensees and others. An NRC interoffice working group prepared a list of human performance information that should be reported for events and the list was based on the Human Performance Investigation Process (HPIP) that had been developed by the NRC as an aid in investigating events. The structure of the HPED was based on that list. The HPED currently includes data on events described in augmented inspection team (AIT) and incident investigation team (IIT) reports from 1990 through 1996, AEOD human performance studies from 1990 through 1993, recent NRR special team inspections, and licensee event reports (LERs) that were prepared for the events. (author)

  11. Interactive analysis of human error factors in NPP operation events

    International Nuclear Information System (INIS)

    Zhang Li; Zou Yanhua; Huang Weigang

    2010-01-01

    Interactive of human error factors in NPP operation events were introduced, and 645 WANO operation event reports from 1999 to 2008 were analyzed, among which 432 were found relative to human errors. After classifying these errors with the Root Causes or Causal Factors, and then applying SPSS for correlation analysis,we concluded: (1) Personnel work practices are restricted by many factors. Forming a good personnel work practices is a systematic work which need supports in many aspects. (2)Verbal communications,personnel work practices, man-machine interface and written procedures and documents play great roles. They are four interaction factors which often come in bundle. If some improvements need to be made on one of them,synchronous measures are also necessary for the others.(3) Management direction and decision process, which are related to management,have a significant interaction with personnel factors. (authors)

  12. Top-down and bottom-up definitions of human failure events in human reliability analysis

    International Nuclear Information System (INIS)

    Boring, Ronald Laurids

    2014-01-01

    In the probabilistic risk assessments (PRAs) used in the nuclear industry, human failure events (HFEs) are determined as a subset of hardware failures, namely those hardware failures that could be triggered by human action or inaction. This approach is top-down, starting with hardware faults and deducing human contributions to those faults. Elsewhere, more traditionally human factors driven approaches would tend to look at opportunities for human errors first in a task analysis and then identify which of those errors is risk significant. The intersection of top-down and bottom-up approaches to defining HFEs has not been carefully studied. Ideally, both approaches should arrive at the same set of HFEs. This question is crucial, however, as human reliability analysis (HRA) methods are generalized to new domains like oil and gas. The HFEs used in nuclear PRAs tend to be top-down - defined as a subset of the PRA - whereas the HFEs used in petroleum quantitative risk assessments (QRAs) often tend to be bottom-up - derived from a task analysis conducted by human factors experts. The marriage of these approaches is necessary in order to ensure that HRA methods developed for top-down HFEs are also sufficient for bottom-up applications.

  13. Proceedings from Specialists Meeting on human performance in operational events

    International Nuclear Information System (INIS)

    1998-01-01

    This conference on human performance in operational events is composed of 34 papers, grouped in 11 sessions. After an invited contribution on the human factor in the nuclear industry, the sessions are: session 1 (Operational events: Human performance in operational events - how to improve it?, Human performance research strategies for human performance, The development of a model of control room operator cognition), session 2 (Operational response: A study of the recovery from 120 events, Empirical study of the influence of organizational and procedural characteristics on team performance in the emergency situation using plant simulators, Cognitive skills and nuclear power plant operational decision making), session 3 (PSA for Probabilistic Safety Analysis: A sensitivity study of human errors in optimizing surveillance test interval (STI) and allowed outage time (AOT) of standby safety system, Analysis of Parks nuclear power plant personnel activity during safety related event sequences, An EDF project to update the Probabilistic Human Reliability Assessment PHRA methodology), session 4 (modelling with ATHEANA: Atheana, a technique for human error analysis, an overview of its methodological basis, Common elements on operational events across technologies, Results of nuclear power plant application of new technique for human error analysis), session 5 (Regulatory practice: US.NRC Research and analysis activities concerning human reliability assessment and human performance evaluation, Introduction of simulator-based examinations and its effects on the nuclear industry, Regulatory monitoring of human performance in PWR operation in France), session 6 (Simulation: Human performance in Bavarian nuclear power plant as a preventive element, Human performance event database, Crew situation awareness, diagnoses and performance in simulated nuclear power plant process disturbances), session 7 (Operator aids: Development of a plant navigation system, Operation system

  14. Experience feedback from event reports: the human contribution

    International Nuclear Information System (INIS)

    Swaton, E.; Tolstykh, V.

    1990-01-01

    Analysis of reported events reveals that in a large number of areas human intervention contributed to the initiation and/or development of these events. Since an accident at any nuclear power plant can have a world-wide effect on public acceptance, the need for attentive and reliable human behavior assumes an even greater significance. The identification of areas where human interaction can have an impact on safe operation is mainly relying on the analysis of events reported to the nuclear community. Any substantial compilation of safety significant operational events such as contained in the IAEA-IRS (Incident Reporting System) is bound to provide valuable and factual insights into problem areas, their origin, development, impact and some remedial actions. Thus a systematic analysis has been carried out on over 200 events where a human contribution could be identified. Some events of particular interest will be discussed and furthermore generic lessons will be presented. In addition the Assessment of Safety Significant Event Technique (ASSET) developed within IAEA which provides a structured methodology to identify not only the direct cause explaining why an individual failed but more important, insights on the root causes explaining why this latent deficiency was not detected earlier through the plant surveillance programme was applied. (author)

  15. Working group of experts on rare events in human error analysis and quantification

    International Nuclear Information System (INIS)

    Goodstein, L.P.

    1977-01-01

    In dealing with the reference problem of rare events in nuclear power plants, the group has concerned itself with the man-machine system and, in particular, with human error analysis and quantification. The Group was requested to review methods of human reliability prediction, to evaluate the extent to which such analyses can be formalized and to establish criteria to be met by task conditions and system design which would permit a systematic, formal analysis. Recommendations are given on the Fessenheim safety system

  16. Investigation of human performance events at French power stations

    International Nuclear Information System (INIS)

    Ghertman, F.; Griffon-Fouco, M.

    1985-01-01

    This paper is concerned with the collection of data on human errors that occur at operating power plants. Three collection methods are used, each relating to a difference level of analysis. (1) Simplified statistical analysis of the causes of human errors: Events which have occurred at operating power plants and which are attributable to human errors are selected. The errors thus identified are analysed briefly and are described by a simplified classification, statistical analysis then being applied to find the principal factors underlying these errors. By way of example, an analysis is given of data on emergency shut-downs involving a human error component that occurred at 900 MW(e) PWR plants during 1982, 1983, 1984. (2) In-depth statistical analysis of the causes of certain human errors: The errors selected are analysed and described by means of a detailed classification. By way of example, the collection and evaluation of data on human errors occurring during periodic tests at a 900 MW(e) power plant over a period of six months are described. (3) In-depth analysis of certain events due to human errors: The events selected are analysed by means of a method which reconstitutes the multicausal aspect of the event and of each human error. By way of example, a description is given of an emergency core cooling required at a 900 MW(e) PWR plant. In conclusion, it is explained how these three methods of collection play complementary roles

  17. A trend analysis of human error events for proactive prevention of accidents. Methodology development and effective utilization

    International Nuclear Information System (INIS)

    Hirotsu, Yuko; Ebisu, Mitsuhiro; Aikawa, Takeshi; Matsubara, Katsuyuki

    2006-01-01

    This paper described methods for analyzing human error events that has been accumulated in the individual plant and for utilizing the result to prevent accidents proactively. Firstly, a categorization framework of trigger action and causal factors of human error events were reexamined, and the procedure to analyze human error events was reviewed based on the framework. Secondly, a method for identifying the common characteristics of trigger action data and of causal factor data accumulated by analyzing human error events was clarified. In addition, to utilize the results of trend analysis effectively, methods to develop teaching material for safety education, to develop the checkpoints for the error prevention and to introduce an error management process for strategic error prevention were proposed. (author)

  18. The action characterization matrix: A link between HERA (Human Events Reference for ATHEANA) and ATHEANA (a technique for human error analysis)

    International Nuclear Information System (INIS)

    Hahn, H.A.

    1997-01-01

    The Technique for Human Error Analysis (ATHEANA) is a newly developed human reliability analysis (HRA) methodology that aims to facilitate better representation and integration of human performance into probabilistic risk assessment (PRA) modeling and quantification by analyzing risk-significant operating experience in the context of existing behavior science models. The fundamental premise of ATHEANA is that error-forcing contexts (EFCs), which refer to combinations of equipment/material conditions and performance shaping factors (PSFs), set up or create the conditions under which unsafe actions (UAs) can occur. ATHEANA is being developed in the context of nuclear power plant (NPP) PRAs, and much of the language used to describe the method and provide examples of its application are specific to that industry. Because ATHEANA relies heavily on the analysis of operational events that have already occurred as a mechanism for generating creative thinking about possible EFCs, a database, called the Human Events Reference for ATHEANA (HERA), has been developed to support the methodology. Los Alamos National Laboratory's (LANL) Human Factors Group has recently joined the ATHEANA project team; LANL is responsible for further developing the database structure and for analyzing additional exemplar operational events for entry into the database. The Action Characterization Matrix (ACM) is conceived as a bridge between the HERA database structure and ATHEANA. Specifically, the ACM allows each unsafe action or human failure event to be characterized according to its representation along each of six different dimensions: system status, initiator status, unsafe action mechanism, information processing stage, equipment/material conditions, and performance shaping factors. This report describes the development of the ACM and provides details on the structure and content of its dimensions

  19. A Description of the Revised ATHEANA (A Technique for Human Event Analysis)

    International Nuclear Information System (INIS)

    FORESTER, JOHN A.; BLEY, DENNIS C.; COOPER, SUSANE; KOLACZKOWSKI, ALAN M.; THOMPSON, CATHERINE; RAMEY-SMITH, ANN; WREATHALL, JOHN

    2000-01-01

    This paper describes the most recent version of a human reliability analysis (HRA) method called ''A Technique for Human Event Analysis'' (ATHEANA). The new version is documented in NUREG-1624, Rev. 1 [1] and reflects improvements to the method based on comments received from a peer review that was held in 1998 (see [2] for a detailed discussion of the peer review comments) and on the results of an initial trial application of the method conducted at a nuclear power plant in 1997 (see Appendix A in [3]). A summary of the more important recommendations resulting from the peer review and trial application is provided and critical and unique aspects of the revised method are discussed

  20. Cause analysis and preventives for human error events in Daya Bay NPP

    International Nuclear Information System (INIS)

    Huang Weigang; Zhang Li

    1998-01-01

    Daya Bay Nuclear Power Plant is put into commercial operation in 1994 Until 1996, there are 368 human error events in operating and maintenance area, occupying 39% of total events. These events occurred mainly in the processes of maintenance, test equipment isolation and system on-line, in particular in refuelling and maintenance. The author analyses root causes for human errorievents, which are mainly operator omission or error procedure deficiency; procedure not followed; lack of training; communication failures; work management inadequacy. The protective measures and treatment principle for human error events are also discussed, and several examples applying them are given. Finally, it is put forward that key to prevent human error event lies in the coordination and management, person in charge of work, and good work habits of staffs

  1. One Size Does Not Fit All: Human Failure Event Decomposition and Task Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Laurids Boring, PhD

    2014-09-01

    In the probabilistic safety assessments (PSAs) used in the nuclear industry, human failure events (HFEs) are determined as a subset of hardware failures, namely those hardware failures that could be triggered or exacerbated by human action or inaction. This approach is top-down, starting with hardware faults and deducing human contributions to those faults. Elsewhere, more traditionally human factors driven approaches would tend to look at opportunities for human errors first in a task analysis and then identify which of those errors is risk significant. The intersection of top-down and bottom-up approaches to defining HFEs has not been carefully studied. Ideally, both approaches should arrive at the same set of HFEs. This question remains central as human reliability analysis (HRA) methods are generalized to new domains like oil and gas. The HFEs used in nuclear PSAs tend to be top-down—defined as a subset of the PSA—whereas the HFEs used in petroleum quantitative risk assessments (QRAs) are more likely to be bottom-up—derived from a task analysis conducted by human factors experts. The marriage of these approaches is necessary in order to ensure that HRA methods developed for top-down HFEs are also sufficient for bottom-up applications. In this paper, I first review top-down and bottom-up approaches for defining HFEs and then present a seven-step guideline to ensure a task analysis completed as part of human error identification decomposes to a level suitable for use as HFEs. This guideline illustrates an effective way to bridge the bottom-up approach with top-down requirements.

  2. Recent adaptive events in human brain revealed by meta-analysis of positively selected genes.

    Directory of Open Access Journals (Sweden)

    Yue Huang

    Full Text Available BACKGROUND AND OBJECTIVES: Analysis of positively-selected genes can help us understand how human evolved, especially the evolution of highly developed cognitive functions. However, previous works have reached conflicting conclusions regarding whether human neuronal genes are over-represented among genes under positive selection. METHODS AND RESULTS: We divided positively-selected genes into four groups according to the identification approaches, compiling a comprehensive list from 27 previous studies. We showed that genes that are highly expressed in the central nervous system are enriched in recent positive selection events in human history identified by intra-species genomic scan, especially in brain regions related to cognitive functions. This pattern holds when different datasets, parameters and analysis pipelines were used. Functional category enrichment analysis supported these findings, showing that synapse-related functions are enriched in genes under recent positive selection. In contrast, immune-related functions, for instance, are enriched in genes under ancient positive selection revealed by inter-species coding region comparison. We further demonstrated that most of these patterns still hold even after controlling for genomic characteristics that might bias genome-wide identification of positively-selected genes including gene length, gene density, GC composition, and intensity of negative selection. CONCLUSION: Our rigorous analysis resolved previous conflicting conclusions and revealed recent adaptation of human brain functions.

  3. Human Events Reference for ATHEANA (HERA) Database Description and Preliminary User's Manual

    International Nuclear Information System (INIS)

    Auflick, J.L.

    1999-01-01

    The Technique for Human Error Analysis (ATHEANA) is a newly developed human reliability analysis (HRA) methodology that aims to facilitate better representation and integration of human performance into probabilistic risk assessment (PRA) modeling and quantification by analyzing risk-significant operating experience in the context of existing behavioral science models. The fundamental premise of ATHEANA is that error forcing contexts (EFCs), which refer to combinations of equipment/material conditions and performance shaping factors (PSFs), set up or create the conditions under which unsafe actions (UAs) can occur. Because ATHEANA relies heavily on the analysis of operational events that have already occurred as a mechanism for generating creative thinking about possible EFCs, a database (db) of analytical operational events, called the Human Events Reference for ATHEANA (HERA), has been developed to support the methodology. This report documents the initial development efforts for HERA

  4. Discrete event simulation versus conventional system reliability analysis approaches

    DEFF Research Database (Denmark)

    Kozine, Igor

    2010-01-01

    Discrete Event Simulation (DES) environments are rapidly developing and appear to be promising tools for building reliability and risk analysis models of safety-critical systems and human operators. If properly developed, they are an alternative to the conventional human reliability analysis models...... and systems analysis methods such as fault and event trees and Bayesian networks. As one part, the paper describes briefly the author’s experience in applying DES models to the analysis of safety-critical systems in different domains. The other part of the paper is devoted to comparing conventional approaches...

  5. A mid-layer model for human reliability analysis: understanding the cognitive causes of human failure events

    International Nuclear Information System (INIS)

    Shen, Song-Hua; Chang, James Y.H.; Boring, Ronald L.; Whaley, April M.; Lois, Erasmia; Langfitt Hendrickson, Stacey M.; Oxstrand, Johanna H.; Forester, John Alan; Kelly, Dana L.; Mosleh, Ali

    2010-01-01

    The Office of Nuclear Regulatory Research (RES) at the US Nuclear Regulatory Commission (USNRC) is sponsoring work in response to a Staff Requirements Memorandum (SRM) directing an effort to establish a single human reliability analysis (HRA) method for the agency or guidance for the use of multiple methods. As part of this effort an attempt to develop a comprehensive HRA qualitative approach is being pursued. This paper presents a draft of the method's middle layer, a part of the qualitative analysis phase that links failure mechanisms to performance shaping factors. Starting with a Crew Response Tree (CRT) that has identified human failure events, analysts identify potential failure mechanisms using the mid-layer model. The mid-layer model presented in this paper traces the identification of the failure mechanisms using the Information-Diagnosis/Decision-Action (IDA) model and cognitive models from the psychological literature. Each failure mechanism is grouped according to a phase of IDA. Under each phase of IDA, the cognitive models help identify the relevant performance shaping factors for the failure mechanism. The use of IDA and cognitive models can be traced through fault trees, which provide a detailed complement to the CRT.

  6. A Mid-Layer Model for Human Reliability Analysis: Understanding the Cognitive Causes of Human Failure Events

    Energy Technology Data Exchange (ETDEWEB)

    Stacey M. L. Hendrickson; April M. Whaley; Ronald L. Boring; James Y. H. Chang; Song-Hua Shen; Ali Mosleh; Johanna H. Oxstrand; John A. Forester; Dana L. Kelly; Erasmia L. Lois

    2010-06-01

    The Office of Nuclear Regulatory Research (RES) is sponsoring work in response to a Staff Requirements Memorandum (SRM) directing an effort to establish a single human reliability analysis (HRA) method for the agency or guidance for the use of multiple methods. As part of this effort an attempt to develop a comprehensive HRA qualitative approach is being pursued. This paper presents a draft of the method’s middle layer, a part of the qualitative analysis phase that links failure mechanisms to performance shaping factors. Starting with a Crew Response Tree (CRT) that has identified human failure events, analysts identify potential failure mechanisms using the mid-layer model. The mid-layer model presented in this paper traces the identification of the failure mechanisms using the Information-Diagnosis/Decision-Action (IDA) model and cognitive models from the psychological literature. Each failure mechanism is grouped according to a phase of IDA. Under each phase of IDA, the cognitive models help identify the relevant performance shaping factors for the failure mechanism. The use of IDA and cognitive models can be traced through fault trees, which provide a detailed complement to the CRT.

  7. Coordination activities of human planners during rescheduling: Case analysis and event handling procedure

    OpenAIRE

    2010-01-01

    Abstract This paper addresses the process of event handling and rescheduling in manufacturing practice. Firms are confronted with many diverse events, like new or changed orders, machine breakdowns, and material shortages. These events influence the feasibility and optimality of schedules, and thus induce rescheduling. In many manufacturing firms, schedules are created by several human planners. Coordination between them is needed to respond to events adequately. In this paper,...

  8. Human factors analysis and design methods for nuclear waste retrieval systems. Volume III. User's guide for the computerized event-tree analysis technique

    International Nuclear Information System (INIS)

    Casey, S.M.; Deretsky, Z.

    1980-08-01

    This document provides detailed instructions for using the Computerized Event-Tree Analysis Technique (CETAT), a program designed to assist a human factors analyst in predicting event probabilities in complex man-machine configurations found in waste retrieval systems. The instructions contained herein describe how to (a) identify the scope of a CETAT analysis, (b) develop operator performance data, (c) enter an event-tree structure, (d) modify a data base, and (e) analyze event paths and man-machine system configurations. Designed to serve as a tool for developing, organizing, and analyzing operator-initiated event probabilities, CETAT simplifies the tasks of the experienced systems analyst by organizing large amounts of data and performing cumbersome and time consuming arithmetic calculations. The principal uses of CETAT in the waste retrieval development project will be to develop models of system reliability and evaluate alternative equipment designs and operator tasks. As with any automated technique, however, the value of the output will be a function of the knowledge and skill of the analyst using the program

  9. Application of human reliability analysis methodology of second generation

    International Nuclear Information System (INIS)

    Ruiz S, T. de J.; Nelson E, P. F.

    2009-10-01

    The human reliability analysis (HRA) is a very important part of probabilistic safety analysis. The main contribution of HRA in nuclear power plants is the identification and characterization of the issues that are brought together for an error occurring in the human tasks that occur under normal operation conditions and those made after abnormal event. Additionally, the analysis of various accidents in history, it was found that the human component has been a contributing factor in the cause. Because of need to understand the forms and probability of human error in the 60 decade begins with the collection of generic data that result in the development of the first generation of HRA methodologies. Subsequently develop methods to include in their models additional performance shaping factors and the interaction between them. So by the 90 mid, comes what is considered the second generation methodologies. Among these is the methodology A Technique for Human Event Analysis (ATHEANA). The application of this method in a generic human failure event, it is interesting because it includes in its modeling commission error, the additional deviations quantification to nominal scenario considered in the accident sequence of probabilistic safety analysis and, for this event the dependency actions evaluation. That is, the generic human failure event was required first independent evaluation of the two related human failure events . So the gathering of the new human error probabilities involves the nominal scenario quantification and cases of significant deviations considered by the potential impact on analyzed human failure events. Like probabilistic safety analysis, with the analysis of the sequences were extracted factors more specific with the highest contribution in the human error probabilities. (Author)

  10. Human Events Reference for ATHEANA (HERA) Database Description and Preliminary User's Manual

    Energy Technology Data Exchange (ETDEWEB)

    Auflick, J.L.

    1999-08-12

    The Technique for Human Error Analysis (ATHEANA) is a newly developed human reliability analysis (HRA) methodology that aims to facilitate better representation and integration of human performance into probabilistic risk assessment (PRA) modeling and quantification by analyzing risk-significant operating experience in the context of existing behavioral science models. The fundamental premise of ATHEANA is that error forcing contexts (EFCs), which refer to combinations of equipment/material conditions and performance shaping factors (PSFs), set up or create the conditions under which unsafe actions (UAs) can occur. Because ATHEANA relies heavily on the analysis of operational events that have already occurred as a mechanism for generating creative thinking about possible EFCs, a database (db) of analytical operational events, called the Human Events Reference for ATHEANA (HERA), has been developed to support the methodology. This report documents the initial development efforts for HERA.

  11. Human events reference for ATHEANA (HERA) database description and preliminary user's manual

    International Nuclear Information System (INIS)

    Auflick, J.L.; Hahn, H.A.; Pond, D.J.

    1998-01-01

    The Technique for Human Error Analysis (ATHEANA) is a newly developed human reliability analysis (HRA) methodology that aims to facilitate better representation and integration of human performance into probabilistic risk assessment (PRA) modeling and quantification by analyzing risk-significant operating experience in the context of existing behavioral science models. The fundamental premise of ATHEANA is that error-forcing contexts (EFCs), which refer to combinations of equipment/material conditions and performance shaping factors (PSFs), set up or create the conditions under which unsafe actions (UAs) can occur. Because ATHEANA relies heavily on the analysis of operational events that have already occurred as a mechanism for generating creative thinking about possible EFCs, a database, called the Human Events Reference for ATHEANA (HERA), has been developed to support the methodology. This report documents the initial development efforts for HERA

  12. A trending database for human performance events

    International Nuclear Information System (INIS)

    Harrison, D.

    1993-01-01

    An effective Operations Experience program includes a standardized methodology for the investigation of unplanned events and a tool capable of retaining investigation data for the purpose of trending analysis. A database used in conjunction with a formalized investigation procedure for the purpose of trending unplanning event data is described. The database follows the structure of INPO's Human Performance Enhancement System for investigations. The database screens duplicate on-line the HPES evaluation Forms. All information pertaining to investigations is collected, retained and entered into the database using these forms. The database will be used for trending analysis to determine if any significant patterns exist, for tracking progress over time both within AECL and against industry standards, and for evaluating the success of corrective actions. Trending information will be used to help prevent similar occurrences

  13. Reducing the occurrence of plant events through improved human performance

    International Nuclear Information System (INIS)

    Ross, T.; Burkhart, A.D.

    1993-01-01

    During a routine control room surveillance, the reactor operator is distracted by an alarming secondary annunciator and a telephone call. When the reactor operator resumes the surveillance, he inadvertently performs the procedural steps out of order. This causes a reportable nuclear event. How can procedure-related human performance problems such as this be prevented? The question is vitally important for the nuclear industry. The U.S. Nuclear Regulatory Commission's Office for Analysis and Evaluation of Operational Data observed, open-quotes With the perceived reduction in the number of events caused by equipment failures, INPO and other industry groups and human performance experts agree that a key to continued improvement in plant performance and safety is improved human performance.close quotes In fact, open-quotes more than 50% of the reportable events occurring at nuclear power plants involve human error.close quotes Prevention (or correction) of a human performance problem is normally based on properly balancing the following three factors: (1) supervisory involvement; (2) personnel training; and (3) procedures. The nuclear industry is implementing a formula known as ACME, which better balances supervisory involvement, personnel training, and procedures. Webster's New World Dictionary defines acme as the highest point, the peak. ACME human performance is the goal: ACME Adherence to and use of procedures; Self-Checking; Management Involvement; and Event Investigations

  14. Human events reference for ATHEANA (HERA) database description and preliminary user`s manual

    Energy Technology Data Exchange (ETDEWEB)

    Auflick, J.L.; Hahn, H.A.; Pond, D.J.

    1998-05-27

    The Technique for Human Error Analysis (ATHEANA) is a newly developed human reliability analysis (HRA) methodology that aims to facilitate better representation and integration of human performance into probabilistic risk assessment (PRA) modeling and quantification by analyzing risk-significant operating experience in the context of existing behavioral science models. The fundamental premise of ATHEANA is that error-forcing contexts (EFCs), which refer to combinations of equipment/material conditions and performance shaping factors (PSFs), set up or create the conditions under which unsafe actions (UAs) can occur. Because ATHEANA relies heavily on the analysis of operational events that have already occurred as a mechanism for generating creative thinking about possible EFCs, a database, called the Human Events Reference for ATHEANA (HERA), has been developed to support the methodology. This report documents the initial development efforts for HERA.

  15. Task types and error types involved in the human-related unplanned reactor trip events

    International Nuclear Information System (INIS)

    Kim, Jae Whan; Park, Jin Kyun

    2008-01-01

    In this paper, the contribution of task types and error types involved in the human-related unplanned reactor trip events that have occurred between 1986 and 2006 in Korean nuclear power plants are analysed in order to establish a strategy for reducing the human-related unplanned reactor trips. Classification systems for the task types, error modes, and cognitive functions are developed or adopted from the currently available taxonomies, and the relevant information is extracted from the event reports or judged on the basis of an event description. According to the analyses from this study, the contributions of the task types are as follows: corrective maintenance (25.7%), planned maintenance (22.8%), planned operation (19.8%), periodic preventive maintenance (14.9%), response to a transient (9.9%), and design/manufacturing/installation (6.9%). According to the analysis of the error modes, error modes such as control failure (22.2%), wrong object (18.5%), omission (14.8%), wrong action (11.1%), and inadequate (8.3%) take up about 75% of the total unplanned trip events. The analysis of the cognitive functions involved in the events indicated that the planning function had the highest contribution (46.7%) to the human actions leading to unplanned reactor trips. This analysis concludes that in order to significantly reduce human-induced or human-related unplanned reactor trips, an aide system (in support of maintenance personnel) for evaluating possible (negative) impacts of planned actions or erroneous actions as well as an appropriate human error prediction technique, should be developed

  16. Task types and error types involved in the human-related unplanned reactor trip events

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Whan; Park, Jin Kyun [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2008-12-15

    In this paper, the contribution of task types and error types involved in the human-related unplanned reactor trip events that have occurred between 1986 and 2006 in Korean nuclear power plants are analysed in order to establish a strategy for reducing the human-related unplanned reactor trips. Classification systems for the task types, error modes, and cognitive functions are developed or adopted from the currently available taxonomies, and the relevant information is extracted from the event reports or judged on the basis of an event description. According to the analyses from this study, the contributions of the task types are as follows: corrective maintenance (25.7%), planned maintenance (22.8%), planned operation (19.8%), periodic preventive maintenance (14.9%), response to a transient (9.9%), and design/manufacturing/installation (6.9%). According to the analysis of the error modes, error modes such as control failure (22.2%), wrong object (18.5%), omission (14.8%), wrong action (11.1%), and inadequate (8.3%) take up about 75% of the total unplanned trip events. The analysis of the cognitive functions involved in the events indicated that the planning function had the highest contribution (46.7%) to the human actions leading to unplanned reactor trips. This analysis concludes that in order to significantly reduce human-induced or human-related unplanned reactor trips, an aide system (in support of maintenance personnel) for evaluating possible (negative) impacts of planned actions or erroneous actions as well as an appropriate human error prediction technique, should be developed.

  17. NPP unusual events: data, analysis and application

    International Nuclear Information System (INIS)

    Tolstykh, V.

    1990-01-01

    Subject of the paper are the IAEA cooperative patterns of unusual events data treatment and utilization of the operating safety experience feedback. The Incident Reporting System (IRS) and the Analysis of Safety Significant Event Team (ASSET) are discussed. The IRS methodology in collection, handling, assessment and dissemination of data on NPP unusual events (deviations, incidents and accidents) occurring during operations, surveillance and maintenance is outlined by the reports gathering and issuing practice, the experts assessment procedures and the parameters of the system. After 7 years of existence the IAEA-IRS contains over 1000 reports and receives 1.5-4% of the total information on unusual events. The author considers the reports only as detailed technical 'records' of events requiring assessment. The ASSET approaches implying an in-depth occurrences analysis directed towards level-1 PSA utilization are commented on. The experts evaluated root causes for the reported events and some trends are presented. Generally, internal events due to unexpected paths of water in the nuclear installations, occurrences related to the integrity of the primary heat transport systems, events associated with the engineered safety systems and events involving human factor represent the large groups deserving close attention. Personal recommendations on how to use the events related information use for NPP safety improvement are given. 2 tabs (R.Ts)

  18. Analysis of Task Types and Error Types of the Human Actions Involved in the Human-related Unplanned Reactor Trip Events

    International Nuclear Information System (INIS)

    Kim, Jae Whan; Park, Jin Kyun; Jung, Won Dea

    2008-02-01

    This report provides the task types and error types involved in the unplanned reactor trip events that have occurred during 1986 - 2006. The events that were caused by the secondary system of the nuclear power plants amount to 67 %, and the remaining 33 % was by the primary system. The contribution of the activities of the plant personnel was identified as the following order: corrective maintenance (25.7 %), planned maintenance (22.8 %), planned operation (19.8 %), periodic preventive maintenance (14.9 %), response to a transient (9.9 %), and design/manufacturing/installation (9.9%). According to the analysis of error modes, the error modes such as control failure (22.2 %), wrong object (18.5 %), omission (14.8 %), wrong action (11.1 %), and inadequate (8.3 %) take up about 75 % of all the unplanned trip events. The analysis of the cognitive functions involved showed that the planning function makes the highest contribution to the human actions leading to unplanned reactor trips, and it is followed by the observation function (23.4%), the execution function (17.8 %), and the interpretation function (10.3 %). The results of this report are to be used as important bases for development of the error reduction measures or development of the error mode prediction system for the test and maintenance tasks in nuclear power plants

  19. Analysis of Task Types and Error Types of the Human Actions Involved in the Human-related Unplanned Reactor Trip Events

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Whan; Park, Jin Kyun; Jung, Won Dea

    2008-02-15

    This report provides the task types and error types involved in the unplanned reactor trip events that have occurred during 1986 - 2006. The events that were caused by the secondary system of the nuclear power plants amount to 67 %, and the remaining 33 % was by the primary system. The contribution of the activities of the plant personnel was identified as the following order: corrective maintenance (25.7 %), planned maintenance (22.8 %), planned operation (19.8 %), periodic preventive maintenance (14.9 %), response to a transient (9.9 %), and design/manufacturing/installation (9.9%). According to the analysis of error modes, the error modes such as control failure (22.2 %), wrong object (18.5 %), omission (14.8 %), wrong action (11.1 %), and inadequate (8.3 %) take up about 75 % of all the unplanned trip events. The analysis of the cognitive functions involved showed that the planning function makes the highest contribution to the human actions leading to unplanned reactor trips, and it is followed by the observation function (23.4%), the execution function (17.8 %), and the interpretation function (10.3 %). The results of this report are to be used as important bases for development of the error reduction measures or development of the error mode prediction system for the test and maintenance tasks in nuclear power plants.

  20. Human based roots of failures in nuclear events investigations

    Energy Technology Data Exchange (ETDEWEB)

    Ziedelis, Stanislovas; Noel, Marc; Strucic, Miodrag [Commission of the European Communities, Petten (Netherlands). European Clearinghouse on Operational Experience Feedback for Nuclear Power Plants

    2012-10-15

    This paper aims for improvement of quality of the event investigations in the nuclear industry through analysis of the existing practices, identifying and removing the existing Human and Organizational Factors (HOF) and management related barriers. It presents the essential results of several studies performed by the European Clearinghouse on Operational Experience. Outcomes of studies are based on survey of currently existing event investigation practices typical for nuclear industry of 12 European countries, as well as on insights from analysis of numerous event investigation reports. System of operational experience feedback from information based on event investigation results is not enough effective to prevent and even to decrease frequency of recurring events due to existing methodological, HOF-related and/or knowledge management related constraints. Besides that, several latent root causes of unsuccessful event investigation are related to weaknesses in safety culture of personnel and managers. These weaknesses include focus on costs or schedule, political manipulation, arrogance, ignorance, entitlement and/or autocracy. Upgrades in safety culture of organization's personnel and its senior management especially seem to be an effective way to improvement. Increasing of competencies, capabilities and level of independency of event investigation teams, elaboration of comprehensive software, ensuring of positive approach, adequate support and impartiality of management could also facilitate for improvement of quality of the event investigations. (orig.)

  1. Human based roots of failures in nuclear events investigations

    International Nuclear Information System (INIS)

    Ziedelis, Stanislovas; Noel, Marc; Strucic, Miodrag

    2012-01-01

    This paper aims for improvement of quality of the event investigations in the nuclear industry through analysis of the existing practices, identifying and removing the existing Human and Organizational Factors (HOF) and management related barriers. It presents the essential results of several studies performed by the European Clearinghouse on Operational Experience. Outcomes of studies are based on survey of currently existing event investigation practices typical for nuclear industry of 12 European countries, as well as on insights from analysis of numerous event investigation reports. System of operational experience feedback from information based on event investigation results is not enough effective to prevent and even to decrease frequency of recurring events due to existing methodological, HOF-related and/or knowledge management related constraints. Besides that, several latent root causes of unsuccessful event investigation are related to weaknesses in safety culture of personnel and managers. These weaknesses include focus on costs or schedule, political manipulation, arrogance, ignorance, entitlement and/or autocracy. Upgrades in safety culture of organization's personnel and its senior management especially seem to be an effective way to improvement. Increasing of competencies, capabilities and level of independency of event investigation teams, elaboration of comprehensive software, ensuring of positive approach, adequate support and impartiality of management could also facilitate for improvement of quality of the event investigations. (orig.)

  2. Identifying and Overcoming Barriers to Effective Consideration of Human and Organisational Factors in Event Analysis and Root Cause Analysis. Workshop Proceedings, September 21-22, 2009, Paris, France

    International Nuclear Information System (INIS)

    2011-01-01

    Nuclear licensees must have effective processes for learning from operating experience in order to manage safety, secure continuous improvement and defend against the potential for repeat events. These processes include root cause analysis (RCA) to identify the underlying causes of events and mechanisms to learn from these analyses and to implement improvements. Correctly identifying and correcting the causes of events will allow lessons to be learned and shared with others in the industry. The treatment of Human and Organisational Factors (HOF) in RCA is of special interest to WGHOF. It is estimated that approximately 60-80% of events in the nuclear industry can be attributed to human and organisational factors. Although the importance of correctly identifying the HOF causes is understood, there is still a tendency for the analysis to focus solely on the technical issues of the event. The history of prominent events across the major hazards sector shows that HOF lessons often fail to be learned. A NEA/CSNI special experts meeting entitled 'Identification of Barriers to Analyzing and Identifying Human and Organisational Factors in Root Cause Analysis' was held at the NEA Headquarters in Paris, France on September 21-22, 2009. A total of 17 participants from 10 countries representing licensee organisations, regulators, international organisations and an independent consultant attended the meeting. The meeting was structured to allow for small group discussions during which a number of themes were explored, followed by plenary discussion. There were also four papers presented which complemented the discussion themes. As set out in the objectives of this work, the participants identified barriers to the effective treatment of HOF in RCA and recommendations to mitigate the effects of these barriers. Many of the barriers and recommendations identified relate to the RCA process in general, not specifically to the treatment of HOF in the RCA process. This is logical, for

  3. Development and application of a methodology for the analysis of significant human related event trends in nuclear power plants

    International Nuclear Information System (INIS)

    Cho, H.Y.

    1981-01-01

    A methodology is developed to identify and flag significant trends related to the safety and availability of U.S. commercial nuclear power plants. The development is intended to aid in reducing likelihood of human errors. To assure that the methodology can be easily adapted to various types of classification schemes of operation data, a data bank classified by the Transient Analysis Classification and Evaluation (TRACE) scheme is selected for the methodology. The significance criteria for human-initiated events affecting the systems and for events caused by human deficiencies were developed. Clustering analysis was used to verify the learning trend in multidimensional histograms. A computer code is developed based on the K-Means algorithm and applied to find the learning period in which error rates are monotonously decreasing with plant age. The Freeman-Tukey (F-T) deviates are used to select generic problems identified by a large positive value (here approximately over 2.0) for the deviate. The identified generic problems are: decision errors which are highly associated with reactor startup operations in the learning period of PWR plants (PWRs), response errors which are highly associated with Secondary Non-Nuclear Systems (SNS) in PWRs, and significant errors affecting systems and which are caused by response action are highly associated with startup reactor mode in BWRS

  4. Accident sequence analysis of human-computer interface design

    International Nuclear Information System (INIS)

    Fan, C.-F.; Chen, W.-H.

    2000-01-01

    It is important to predict potential accident sequences of human-computer interaction in a safety-critical computing system so that vulnerable points can be disclosed and removed. We address this issue by proposing a Multi-Context human-computer interaction Model along with its analysis techniques, an Augmented Fault Tree Analysis, and a Concurrent Event Tree Analysis. The proposed augmented fault tree can identify the potential weak points in software design that may induce unintended software functions or erroneous human procedures. The concurrent event tree can enumerate possible accident sequences due to these weak points

  5. Knowledge-base for the new human reliability analysis method, A Technique for Human Error Analysis (ATHEANA)

    International Nuclear Information System (INIS)

    Cooper, S.E.; Wreathall, J.; Thompson, C.M., Drouin, M.; Bley, D.C.

    1996-01-01

    This paper describes the knowledge base for the application of the new human reliability analysis (HRA) method, a ''A Technique for Human Error Analysis'' (ATHEANA). Since application of ATHEANA requires the identification of previously unmodeled human failure events, especially errors of commission, and associated error-forcing contexts (i.e., combinations of plant conditions and performance shaping factors), this knowledge base is an essential aid for the HRA analyst

  6. Analysis of loss of offsite power events reported in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Volkanovski, Andrija, E-mail: Andrija.VOLKANOVSKI@ec.europa.eu [European Commission, Joint Research Centre, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Ballesteros Avila, Antonio; Peinador Veira, Miguel [European Commission, Joint Research Centre, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Kančev, Duško [Kernkraftwerk Goesgen-Daeniken AG, CH-4658 Daeniken (Switzerland); Maqua, Michael [Gesellschaft für Anlagen-und-Reaktorsicherheit (GRS) gGmbH, Schwertnergasse 1, 50667 Köln (Germany); Stephan, Jean-Luc [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), BP 17 – 92262 Fontenay-aux-Roses Cedex (France)

    2016-10-15

    Highlights: • Loss of offsite power events were identified in four databases. • Engineering analysis of relevant events was done. • The dominant root cause for LOOP are human failures. • Improved maintenance procedures can decrease the number of LOOP events. - Abstract: This paper presents the results of analysis of the loss of offsite power events (LOOP) in four databases of operational events. The screened databases include: the Gesellschaft für Anlagen und Reaktorsicherheit mbH (GRS) and Institut de Radioprotection et de Sûreté Nucléaire (IRSN) databases, the IAEA International Reporting System for Operating Experience (IRS) and the U.S. Licensee Event Reports (LER). In total 228 relevant loss of offsite power events were identified in the IRSN database, 190 in the GRS database, 120 in U.S. LER and 52 in IRS database. Identified events were classified in predefined categories. Obtained results show that the largest percentage of LOOP events is registered during On power operational mode and lasted for two minutes or more. The plant centered events is the main contributor to LOOP events identified in IRSN, GRS and IAEA IRS database. The switchyard centered events are the main contributor in events registered in the NRC LER database. The main type of failed equipment is switchyard failures in IRSN and IAEA IRS, main or secondary lines in NRC LER and busbar failures in GRS database. The dominant root cause for the LOOP events are human failures during test, inspection and maintenance followed by human failures due to the insufficient or wrong procedures. The largest number of LOOP events resulted in reactor trip followed by EDG start. The actions that can result in reduction of the number of LOOP events and minimize consequences on plant safety are identified and presented.

  7. A Quantitative Index to Support Recurrence Prevention Plans of Human-Related Events

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yochan; Park, Jinkyun; Jung, Wondea [KAERI, Daejeon (Korea, Republic of); Kim, Do Sam; Lee, Durk Hun [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2015-05-15

    In Korea, HuRAM+ (Human related event Root cause Analysis Method plus) was developed to scrutinize the causes of the human-related events. The information of the human-related events investigated by the HuRAM+ method has been also managed by a database management system, R-tracer. It is obvious that accumulating data of human error causes aims to support plans that reduce recurrences of similar events. However, in spite of the efforts for the development of the human error database, it was indicated that the database does not provide useful empirical basis for establishment of the recurrence prevention plans, because the framework to interpret the collected data and apply the insights from the data into the prevention plants has not been developed yet. In this paper, in order to support establishment of the recurrence prevention plans, a quantitative index, Human Error Repeat Interval (HERI), was proposed and its applications to human error prevention were introduced. In this paper, a quantitative index, the HERI was proposed and the statistics of HERIs were introduced. These estimations can be employed to evaluate effects of recurrence prevention plans to human errors. If a mean HERI score is low and the linear trend is not positive, it can be suspected that the recurrence prevention plans applied every human-related event has not been effectively propagated. For reducing repetitive error causes, the system design or operational culture can be reviewed. If there is a strong and negative trend, systematic investigation of the root causes behind these trends is required. Likewise, we expect that the HERI index will provide significant basis for establishing or adjusting prevention plans of human errors. The accurate estimation and application of HERI scores is expected to be done after accumulating more data. When a scatter plot of HERIs is fitted by two or more models, a statistical model selection method can be employed. Some criteria have been introduced by

  8. A Quantitative Index to Support Recurrence Prevention Plans of Human-Related Events

    International Nuclear Information System (INIS)

    Kim, Yochan; Park, Jinkyun; Jung, Wondea; Kim, Do Sam; Lee, Durk Hun

    2015-01-01

    In Korea, HuRAM+ (Human related event Root cause Analysis Method plus) was developed to scrutinize the causes of the human-related events. The information of the human-related events investigated by the HuRAM+ method has been also managed by a database management system, R-tracer. It is obvious that accumulating data of human error causes aims to support plans that reduce recurrences of similar events. However, in spite of the efforts for the development of the human error database, it was indicated that the database does not provide useful empirical basis for establishment of the recurrence prevention plans, because the framework to interpret the collected data and apply the insights from the data into the prevention plants has not been developed yet. In this paper, in order to support establishment of the recurrence prevention plans, a quantitative index, Human Error Repeat Interval (HERI), was proposed and its applications to human error prevention were introduced. In this paper, a quantitative index, the HERI was proposed and the statistics of HERIs were introduced. These estimations can be employed to evaluate effects of recurrence prevention plans to human errors. If a mean HERI score is low and the linear trend is not positive, it can be suspected that the recurrence prevention plans applied every human-related event has not been effectively propagated. For reducing repetitive error causes, the system design or operational culture can be reviewed. If there is a strong and negative trend, systematic investigation of the root causes behind these trends is required. Likewise, we expect that the HERI index will provide significant basis for establishing or adjusting prevention plans of human errors. The accurate estimation and application of HERI scores is expected to be done after accumulating more data. When a scatter plot of HERIs is fitted by two or more models, a statistical model selection method can be employed. Some criteria have been introduced by

  9. Evaluation of the reliability concerning the identification of human factors as contributing factors by a computer supported event analysis (CEA)

    International Nuclear Information System (INIS)

    Wilpert, B.; Maimer, H.; Loroff, C.

    2000-01-01

    The project's objectives are the evaluation of the reliability concerning the identification of Human Factors as contributing factors by a computer supported event analysis (CEA). CEA is a computer version of SOL (Safety through Organizational Learning). Parts of the first step were interviews with experts from the nuclear power industry and the evaluation of existing computer supported event analysis methods. This information was combined to a requirement profile for the CEA software. The next step contained the implementation of the software in an iterative process of evaluation. The completion of this project was the testing of the CEA software. As a result the testing demonstrated that it is possible to identify contributing factors with CEA validly. In addition, CEA received a very positive feedback from the experts. (orig.) [de

  10. Probabilistic analysis of extreme wind events

    Energy Technology Data Exchange (ETDEWEB)

    Chaviaropoulos, P.K. [Center for Renewable Energy Sources (CRES), Pikermi Attikis (Greece)

    1997-12-31

    A vital task in wind engineering and meterology is to understand, measure, analyse and forecast extreme wind conditions, due to their significant effects on human activities and installations like buildings, bridges or wind turbines. The latest version of the IEC standard (1996) pays particular attention to the extreme wind events that have to be taken into account when designing or certifying a wind generator. Actually, the extreme wind events within a 50 year period are those which determine the ``static`` design of most of the wind turbine components. The extremes which are important for the safety of wind generators are those associated with the so-called ``survival wind speed``, the extreme operating gusts and the extreme wind direction changes. A probabilistic approach for the analysis of these events is proposed in this paper. Emphasis is put on establishing the relation between extreme values and physically meaningful ``site calibration`` parameters, like probability distribution of the annual wind speed, turbulence intensity and power spectra properties. (Author)

  11. Investigations on human error hazards in recent unintended trip events of Korean nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sa Kil; Jang, Tong Il; Lee, Yong Hee; Shin, Kwang Hyeon [KAERI, Daejeon (Korea, Republic of)

    2012-10-15

    According to the Operational Performance Information System (OPIS) which has been operated to improve the public understanding by the KINS (Korea Institute of Nuclear Safety), unintended trip events by mainly human errors counted up to 38 cases (18.7%) from 2000 to 2011. Although the Nuclear Power Plant (NPP) industry in Korea has been making efforts to reduce the human errors which have largely contributed to trip events, the human error rate might keep increasing. Interestingly, digital based I and C systems is the one of the reduction factors of unintended reactor trips. Human errors, however, have occurred due to the digital based I and C systems because those systems require new or changed behaviors to the NPP operators. Therefore, it is necessary that the investigations of human errors consider a new methodology to find not only tangible behavior but also intangible behavior such as organizational behaviors. In this study we investigated human errors to find latent factors such as decisions and conditions in the all of the unintended reactor trip events during last dozen years. To find them, we applied the HFACS (Human Factors Analysis and Classification System) which is a commonly utilized tool for investigating human contributions to aviation accidents under a widespread evaluation scheme. The objective of this study is to find latent factors behind of human errors in nuclear reactor trip events. Therefore, a method to investigate unintended trip events by human errors and the results will be discussed in more detail.

  12. Investigations on human error hazards in recent unintended trip events of Korean nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Sa Kil; Jang, Tong Il; Lee, Yong Hee; Shin, Kwang Hyeon

    2012-01-01

    According to the Operational Performance Information System (OPIS) which has been operated to improve the public understanding by the KINS (Korea Institute of Nuclear Safety), unintended trip events by mainly human errors counted up to 38 cases (18.7%) from 2000 to 2011. Although the Nuclear Power Plant (NPP) industry in Korea has been making efforts to reduce the human errors which have largely contributed to trip events, the human error rate might keep increasing. Interestingly, digital based I and C systems is the one of the reduction factors of unintended reactor trips. Human errors, however, have occurred due to the digital based I and C systems because those systems require new or changed behaviors to the NPP operators. Therefore, it is necessary that the investigations of human errors consider a new methodology to find not only tangible behavior but also intangible behavior such as organizational behaviors. In this study we investigated human errors to find latent factors such as decisions and conditions in the all of the unintended reactor trip events during last dozen years. To find them, we applied the HFACS (Human Factors Analysis and Classification System) which is a commonly utilized tool for investigating human contributions to aviation accidents under a widespread evaluation scheme. The objective of this study is to find latent factors behind of human errors in nuclear reactor trip events. Therefore, a method to investigate unintended trip events by human errors and the results will be discussed in more detail

  13. Trend analysis of nuclear reactor automatic trip events subjected to operator's human error at United States nuclear power plants

    International Nuclear Information System (INIS)

    Takagawa, Kenichi

    2009-01-01

    Trends in nuclear reactor automatic trip events due to human errors during plant operating mode have been analyzed by extracting 20 events which took place in the United States during the period of seven years from 2002 to 2008, cited in the LERs (Licensee Event Reports) submitted to the US Nuclear Regulatory Commission (NRC). It was shown that the yearly number of events was relatively large before 2005, and thereafter the number decreased. A period of stable operation, in which the yearly number was kept very small, continued for about three years, and then the yearly number turned to increase again. Before 2005, automatic trip events occurred more frequently during periodic inspections or start-up/shut-down operations. The recent trends, however, indicate that trip events became more frequent due to human errors during daily operations. Human errors were mostly caused by the self-conceit and carelessness of operators through the whole period. The before mentioned trends in the yearly number of events might be explained as follows. The decrease in the automatic trip events is attributed to sharing trouble information, leading as a consequence to improvement of the manual and training for the operations which have a higher potential risk of automatic trip. Then, while the period of stable operation continued, some operators came to pay less attention to preventing human errors and not interest in the training, leading to automatic trip events in reality due to miss-operation. From these analyses on trouble experiences in the US, we learnt the followings to prevent the occurrence similar troubles in Japan: Operators should be thoroughly skilled in basic actions to prevent human errors as persons concerned. And it should be further emphasized that they should elaborate by imaging actual plant operations even though the simulator training gives them successful experiences. (author)

  14. Short template switch events explain mutation clusters in the human genome.

    Science.gov (United States)

    Löytynoja, Ari; Goldman, Nick

    2017-06-01

    Resequencing efforts are uncovering the extent of genetic variation in humans and provide data to study the evolutionary processes shaping our genome. One recurring puzzle in both intra- and inter-species studies is the high frequency of complex mutations comprising multiple nearby base substitutions or insertion-deletions. We devised a generalized mutation model of template switching during replication that extends existing models of genome rearrangement and used this to study the role of template switch events in the origin of short mutation clusters. Applied to the human genome, our model detects thousands of template switch events during the evolution of human and chimp from their common ancestor and hundreds of events between two independently sequenced human genomes. Although many of these are consistent with a template switch mechanism previously proposed for bacteria, our model also identifies new types of mutations that create short inversions, some flanked by paired inverted repeats. The local template switch process can create numerous complex mutation patterns, including hairpin loop structures, and explains multinucleotide mutations and compensatory substitutions without invoking positive selection, speculative mechanisms, or implausible coincidence. Clustered sequence differences are challenging for current mapping and variant calling methods, and we show that many erroneous variant annotations exist in human reference data. Local template switch events may have been neglected as an explanation for complex mutations because of biases in commonly used analyses. Incorporation of our model into reference-based analysis pipelines and comparisons of de novo assembled genomes will lead to improved understanding of genome variation and evolution. © 2017 Löytynoja and Goldman; Published by Cold Spring Harbor Laboratory Press.

  15. Human error probability estimation using licensee event reports

    International Nuclear Information System (INIS)

    Voska, K.J.; O'Brien, J.N.

    1984-07-01

    Objective of this report is to present a method for using field data from nuclear power plants to estimate human error probabilities (HEPs). These HEPs are then used in probabilistic risk activities. This method of estimating HEPs is one of four being pursued in NRC-sponsored research. The other three are structured expert judgment, analysis of training simulator data, and performance modeling. The type of field data analyzed in this report is from Licensee Event reports (LERs) which are analyzed using a method specifically developed for that purpose. However, any type of field data or human errors could be analyzed using this method with minor adjustments. This report assesses the practicality, acceptability, and usefulness of estimating HEPs from LERs and comprehensively presents the method for use

  16. Human-assisted sound event recognition for home service robots.

    Science.gov (United States)

    Do, Ha Manh; Sheng, Weihua; Liu, Meiqin

    This paper proposes and implements an open framework of active auditory learning for a home service robot to serve the elderly living alone at home. The framework was developed to realize the various auditory perception capabilities while enabling a remote human operator to involve in the sound event recognition process for elderly care. The home service robot is able to estimate the sound source position and collaborate with the human operator in sound event recognition while protecting the privacy of the elderly. Our experimental results validated the proposed framework and evaluated auditory perception capabilities and human-robot collaboration in sound event recognition.

  17. Notes on human error analysis and prediction

    International Nuclear Information System (INIS)

    Rasmussen, J.

    1978-11-01

    The notes comprise an introductory discussion of the role of human error analysis and prediction in industrial risk analysis. Following this introduction, different classes of human errors and role in industrial systems are mentioned. Problems related to the prediction of human behaviour in reliability and safety analysis are formulated and ''criteria for analyzability'' which must be met by industrial systems so that a systematic analysis can be performed are suggested. The appendices contain illustrative case stories and a review of human error reports for the task of equipment calibration and testing as found in the US Licensee Event Reports. (author)

  18. Integrating human factors into process hazard analysis

    International Nuclear Information System (INIS)

    Kariuki, S.G.; Loewe, K.

    2007-01-01

    A comprehensive process hazard analysis (PHA) needs to address human factors. This paper describes an approach that systematically identifies human error in process design and the human factors that influence its production and propagation. It is deductive in nature and therefore considers human error as a top event. The combinations of different factors that may lead to this top event are analysed. It is qualitative in nature and is used in combination with other PHA methods. The method has an advantage because it does not look at the operator error as the sole contributor to the human failure within a system but a combination of all underlying factors

  19. Representation of human behaviour in probabilistic safety analysis

    International Nuclear Information System (INIS)

    Whittingham, R.B.

    1991-01-01

    This paper provides an overview of the representation of human behaviour in probabilistic safety assessment. Human performance problems which may result in errors leading to accidents are considered in terms of methods of identification using task analysis, screening analysis of critical errors, representation and quantification of human errors in fault trees and event trees and error reduction measures. (author) figs., tabs., 43 refs

  20. Analysis of human performance in KHNP NPPs

    International Nuclear Information System (INIS)

    Tae, Sung Eun

    2004-01-01

    The most important thing in the management of nuclear power plant is safety. One of the key factors to enhance the safety is to analyze human performance and to reflect the results on the practical plant operation. KHNP NPPs experienced human errors in the fields of operation and maintenance. The human errors need to be analyzed and, necessary corrective actions according to the causes should be made to prevent the same event or similar events. Therefore we'd like to introduce the procedure of K-HPES(KHNP-Human Performance Enhancement System) and the results of analysis of HPES reports produced in 2002 and 2003

  1. Human event observations in the individual plant examinations

    Energy Technology Data Exchange (ETDEWEB)

    Forester, J. [Sandia National Labs., Albuquerque, NM (United States)

    1995-04-01

    A major objective of the Individual Plant Examination Insights Program is to identify the important determinants of core damage frequency for the different reactor and containment types and plant designs as indicated in the IPEs. The human reliability analysis is a critical component of the probabilistic risk assessments which were done for the IPEs. The determination and selection of human actions for incorporation into the event and fault tree models and the quantification of their failure probabilities can have an important impact on the resulting estimates of CDF and risk. Two important goals of the NRCs IPE Insights Program are (1) to determine the extent to which human actions and their corresponding failure probabilities influenced the results of the IPEs and (2) to identify which factors played significant roles in determining the differences and similarities in the results of the HRA analyses across the different plants. To obtain the relevant information, the NRC`s IPE database, which contains information on plant design, CDF, and containment performance obtained from the IPEs, was used in conjunction with a systematic examination of the HRA analyses and results from the IPEs. Regarding the extent to which the results of the HRA analyses were significant contributors to the plants` CDFs, examinations of several different measures indicated that while individual human actions could have important influences on CDF for particular initiators, the HRA results did not appear to be the most significant driver of plant risk. Another finding was that while there were relatively wide variations in the calculated human error probabilities for similar events across plants, there was no evidence for any systematic variation as a function of the HRA methods used in the analyses. Much of the variability in HEP values can be explained by differences in plant characteristics and sequence-specific factors. Details of these results and other findings are discussed.

  2. Human event observations in the individual plant examinations

    International Nuclear Information System (INIS)

    Forester, J.

    1995-01-01

    A major objective of the Individual Plant Examination Insights Program is to identify the important determinants of core damage frequency for the different reactor and containment types and plant designs as indicated in the IPEs. The human reliability analysis is a critical component of the probabilistic risk assessments which were done for the IPEs. The determination and selection of human actions for incorporation into the event and fault tree models and the quantification of their failure probabilities can have an important impact on the resulting estimates of CDF and risk. Two important goals of the NRCs IPE Insights Program are (1) to determine the extent to which human actions and their corresponding failure probabilities influenced the results of the IPEs and (2) to identify which factors played significant roles in determining the differences and similarities in the results of the HRA analyses across the different plants. To obtain the relevant information, the NRC's IPE database, which contains information on plant design, CDF, and containment performance obtained from the IPEs, was used in conjunction with a systematic examination of the HRA analyses and results from the IPEs. Regarding the extent to which the results of the HRA analyses were significant contributors to the plants' CDFs, examinations of several different measures indicated that while individual human actions could have important influences on CDF for particular initiators, the HRA results did not appear to be the most significant driver of plant risk. Another finding was that while there were relatively wide variations in the calculated human error probabilities for similar events across plants, there was no evidence for any systematic variation as a function of the HRA methods used in the analyses. Much of the variability in HEP values can be explained by differences in plant characteristics and sequence-specific factors. Details of these results and other findings are discussed

  3. Human event observations in the individual plant examinations

    International Nuclear Information System (INIS)

    Forester, J.

    1995-01-01

    A major objective of the Nuclear Regulatory Commission's (NRC) Individual Plant Examination (IPE) Insights Program is to identify the important determinants of core damage frequency (CDF) for the different reactor and containment types and plant designs as indicated in the IPEs. The human reliability analysis (HRA) is a critical component of the probabilistic risk assessments (PRAS) which were done for the IPES. The determination and selection of human actions for incorporation into the event and fault tree models and the quantification of their failure probabilities can have an important impact on the resulting estimates of CDF and risk. Therefore, two important goals of the NRCs IPE Insights Program are (1) to determine the extent to which human actions and their corresponding failure probabilities influenced the results of the IPEs and (2) to identify which factors played significant roles in determining the differences and similarities in the results of the HRA analyses across the different plants. To obtain the relevant information, the NRC's IPE database, which contains information on plant design, CDF, and containment performance obtained from the IPES, was used in conjunction with a systematic examination of the HRA analyses and results from the IPES. Regarding the extent to which the results of the HRA analyses were significant contributors to the plants' CDFs, examinations of several different measures indicated that while individual human actions could have important influences on CDF for particular initiators, the HRA results did not appear to be the most significant driver of plant risk (CDF). Another finding was that while there were relatively wide variations in the calculated human error probabilities (HEPs) for similar events across plants, there was no evidence for any systematic variation as a function of the HRA methods used in the analyses

  4. MGR External Events Hazards Analysis

    International Nuclear Information System (INIS)

    Booth, L.

    1999-01-01

    The purpose and objective of this analysis is to apply an external events Hazards Analysis (HA) to the License Application Design Selection Enhanced Design Alternative 11 [(LADS EDA II design (Reference 8.32))]. The output of the HA is called a Hazards List (HL). This analysis supersedes the external hazards portion of Rev. 00 of the PHA (Reference 8.1). The PHA for internal events will also be updated to the LADS EDA II design but under a separate analysis. Like the PHA methodology, the HA methodology provides a systematic method to identify potential hazards during the 100-year Monitored Geologic Repository (MGR) operating period updated to reflect the EDA II design. The resulting events on the HL are candidates that may have potential radiological consequences as determined during Design Basis Events (DBEs) analyses. Therefore, the HL that results from this analysis will undergo further screening and analysis based on the criteria that apply during the performance of DBE analyses

  5. Probabilistic analysis of external events with focus on the Fukushima event

    International Nuclear Information System (INIS)

    Kollasko, Heiko; Jockenhoevel-Barttfeld, Mariana; Klapp, Ulrich

    2014-01-01

    External hazards are those natural or man-made hazards to a site and facilities that are originated externally to both the site and its processes, i.e. the duty holder may have very little or no control over the hazard. External hazards can have the potential of causing initiating events at the plant, typically transients like e.g., loss of offsite power. Simultaneously, external events may affect safety systems required to control the initiating event and, where applicable, also back-up systems implemented for risk-reduction. The plant safety may especially be threatened when loads from external hazards exceed the load assumptions considered in the design of safety-related systems, structures and components. Another potential threat is given by hazards inducing initiating events not considered in the safety demonstration otherwise. An example is loss of offsite power combined with prolonged plant isolation. Offsite support, e.g., delivery of diesel fuel oil, usually credited in the deterministic safety analysis may not be possible in this case. As the Fukushima events have shown, the biggest threat is likely given by hazards inducing both effects. Such hazards may well be dominant risk contributors even if their return period is very high. In order to identify relevant external hazards for a certain Nuclear Power Plant (NPP) location, a site specific screening analysis is performed, both for single events and for combinations of external events. As a result of the screening analysis, risk significant and therefore relevant (screened-in) single external events and combinations of them are identified for a site. The screened-in events are further considered in a detailed event tree analysis in the frame of the Probabilistic Safety Analysis (PSA) to calculate the core damage/large release frequency resulting from each relevant external event or from each relevant combination. Screening analyses of external events performed at AREVA are based on the approach provided

  6. Human failure event analysis and precautionary methods and their application to reactor system

    International Nuclear Information System (INIS)

    Zhang Li; Huang Shudong; Wang Yiqun; Gao Wenyu; Zhang Jin

    2003-01-01

    Making use of human factor engineering, control science and safety science and adopting the method of systemically collection and doing research work factually, the authors analyze the problem and tendency of human factor science, the classification system, the formation, the quantitative appraisal, data collection and data bank, the effect and influence of organization management, the root cause analysis technology, and human error failure mode and effect and criticality analysis, the method and strategy of defense-in-depth for preventing human-initiated accident. The human factor accidents theory and mechanism are constructed. All of the above was successfully applied to Daya Bay Nuclear Power Station and Lingao Nuclear Power Station. (authors)

  7. IDHEAS – A NEW APPROACH FOR HUMAN RELIABILITY ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    G. W. Parry; J.A Forester; V.N. Dang; S. M. L. Hendrickson; M. Presley; E. Lois; J. Xing

    2013-09-01

    This paper describes a method, IDHEAS (Integrated Decision-Tree Human Event Analysis System) that has been developed jointly by the US NRC and EPRI as an improved approach to Human Reliability Analysis (HRA) that is based on an understanding of the cognitive mechanisms and performance influencing factors (PIFs) that affect operator responses. The paper describes the various elements of the method, namely the performance of a detailed cognitive task analysis that is documented in a crew response tree (CRT), and the development of the associated time-line to identify the critical tasks, i.e. those whose failure results in a human failure event (HFE), and an approach to quantification that is based on explanations of why the HFE might occur.

  8. Identification of human-induced initiating events in the low power and shutdown operation using the commission error search and assessment method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yong Chan; Kim, Jong Hyun [KEPCO International Nuclear Graduate School (KINGS), Ulsan (Korea, Republic of)

    2015-03-15

    Human-induced initiating events, also called Category B actions in human reliability analysis, are operator actions that may lead directly to initiating events. Most conventional probabilistic safety analyses typically assume that the frequency of initiating events also includes the probability of human-induced initiating events. However, some regulatory documents require Category B actions to be specifically analyzed and quantified in probabilistic safety analysis. An explicit modeling of Category B actions could also potentially lead to important insights into human performance in terms of safety. However, there is no standard procedure to identify Category B actions. This paper describes a systematic procedure to identify Category B actions for low power and shutdown conditions. The procedure includes several steps to determine operator actions that may lead to initiating events in the low power and shutdown stages. These steps are the selection of initiating events, the selection of systems or components, the screening of unlikely operating actions, and the quantification of initiating events. The procedure also provides the detailed instruction for each step, such as operator's action, information required, screening rules, and the outputs. Finally, the applicability of the suggested approach is also investigated by application to a plant example.

  9. Fifty Years of THERP and Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring

    2012-06-01

    In 1962 at a Human Factors Society symposium, Alan Swain presented a paper introducing a Technique for Human Error Rate Prediction (THERP). This was followed in 1963 by a Sandia Laboratories monograph outlining basic human error quantification using THERP and, in 1964, by a special journal edition of Human Factors on quantification of human performance. Throughout the 1960s, Swain and his colleagues focused on collecting human performance data for the Sandia Human Error Rate Bank (SHERB), primarily in connection with supporting the reliability of nuclear weapons assembly in the US. In 1969, Swain met with Jens Rasmussen of Risø National Laboratory and discussed the applicability of THERP to nuclear power applications. By 1975, in WASH-1400, Swain had articulated the use of THERP for nuclear power applications, and the approach was finalized in the watershed publication of the NUREG/CR-1278 in 1983. THERP is now 50 years old, and remains the most well known and most widely used HRA method. In this paper, the author discusses the history of THERP, based on published reports and personal communication and interviews with Swain. The author also outlines the significance of THERP. The foundations of human reliability analysis are found in THERP: human failure events, task analysis, performance shaping factors, human error probabilities, dependence, event trees, recovery, and pre- and post-initiating events were all introduced in THERP. While THERP is not without its detractors, and it is showing signs of its age in the face of newer technological applications, the longevity of THERP is a testament of its tremendous significance. THERP started the field of human reliability analysis. This paper concludes with a discussion of THERP in the context of newer methods, which can be seen as extensions of or departures from Swain’s pioneering work.

  10. Distinctiveness enhances long-term event memory in non-human primates, irrespective of reinforcement.

    Science.gov (United States)

    Lewis, Amy; Call, Josep; Berntsen, Dorthe

    2017-08-01

    Non-human primates are capable of recalling events that occurred as long as 3 years ago, and are able to distinguish between similar events; akin to human memory. In humans, distinctiveness enhances memory for events, however, it is unknown whether the same occurs in non-human primates. As such, we tested three great ape species on their ability to remember an event that varied in distinctiveness. Across three experiments, apes witnessed a baiting event in which one of three identical containers was baited with food. After a delay of 2 weeks, we tested their memory for the location of the baited container. Apes failed to recall the baited container when the event was undistinctive (Experiment 1), but were successful when it was distinctive (Experiment 2), although performance was equally good in a less-distinctive condition. A third experiment (Experiment 3) confirmed that distinctiveness, independent of reinforcement, was a consistent predictor of performance. These findings suggest that distinctiveness may enhance memory for events in non-human primates in the same way as in humans, and provides further evidence of basic similarities between the ways apes and humans remember past events. © 2017 Wiley Periodicals, Inc.

  11. Using variable transformations to perform common event analysis

    International Nuclear Information System (INIS)

    Worrell, R.B.

    1977-01-01

    Any analytical method for studying the effect of common events on the behavior of a system is considered as being a form of common event analysis. The particular common events that are involved often represent quite different phenomena, and this has led to the development of different kinds of common event analysis. For example, common mode failure analysis, common cause analysis, critical location analysis, etc., are all different kinds of common event analysis for which the common events involved represent different phenomena. However, the problem that must be solved for each of these different kinds of common event analysis is essentially the same: Determine the effect of common events on the behavior of a system. Thus, a technique that is useful in achieving one kind of common event analysis is often useful in achieving other kinds of common event analysis

  12. Flexible Human Behavior Analysis Framework for Video Surveillance Applications

    Directory of Open Access Journals (Sweden)

    Weilun Lao

    2010-01-01

    Full Text Available We study a flexible framework for semantic analysis of human motion from surveillance video. Successful trajectory estimation and human-body modeling facilitate the semantic analysis of human activities in video sequences. Although human motion is widely investigated, we have extended such research in three aspects. By adding a second camera, not only more reliable behavior analysis is possible, but it also enables to map the ongoing scene events onto a 3D setting to facilitate further semantic analysis. The second contribution is the introduction of a 3D reconstruction scheme for scene understanding. Thirdly, we perform a fast scheme to detect different body parts and generate a fitting skeleton model, without using the explicit assumption of upright body posture. The extension of multiple-view fusion improves the event-based semantic analysis by 15%–30%. Our proposed framework proves its effectiveness as it achieves a near real-time performance (13–15 frames/second and 6–8 frames/second for monocular and two-view video sequences.

  13. Common Elements in Operational Events across Technologies

    International Nuclear Information System (INIS)

    Bley, Dennis C.; Wreathall, John; Cooper, Susan E.

    1998-01-01

    The ATHEANA project, sponsored by the US NRC, began as a study of operational events during low power and shutdown conditions at US commercial nuclear power plants. The purpose was to develop an approach for human reliability analysis that is supported by the experience; i.e., with the history of operational events. As the analysis of operational events progressed, a multidisciplinary framework evolved that can structure the analysis, highlighting significant aspects of each event. The ATHEANA multidisciplinary framework has been used as the basis for retrospective analysis of human performance in operational events in the nuclear power, chemical process, aviation, and medical technologies. The results of these analyses are exemplified by three operational events from different industries. Attention is drawn to those common elements in serious operational events that have negative impacts on human performance. (authors)

  14. How They Move Reveals What Is Happening: Understanding the Dynamics of Big Events from Human Mobility Pattern

    Directory of Open Access Journals (Sweden)

    Jean Damascène Mazimpaka

    2017-01-01

    Full Text Available The context in which a moving object moves contributes to the movement pattern observed. Likewise, the movement pattern reflects the properties of the movement context. In particular, big events influence human mobility depending on the dynamics of the events. However, this influence has not been explored to understand big events. In this paper, we propose a methodology for learning about big events from human mobility pattern. The methodology involves extracting and analysing the stopping, approaching, and moving-away interactions between public transportation vehicles and the geographic context. The analysis is carried out at two different temporal granularity levels to discover global and local patterns. The results of evaluating this methodology on bus trajectories demonstrate that it can discover occurrences of big events from mobility patterns, roughly estimate the event start and end time, and reveal the temporal patterns of arrival and departure of event attendees. This knowledge can be usefully applied in transportation and event planning and management.

  15. Internal event analysis of Laguna Verde Unit 1 Nuclear Power Plant. System Analysis

    International Nuclear Information System (INIS)

    Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R.

    1993-01-01

    The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the I nternal Event Analysis of Laguna Verde Unit 1 Nuclear Power Plant , CNSNS-TR-004, in five volumes. The reports are organized as follows: CNSNS-TR-004 Volume 1: Introduction and Methodology. CNSNS-TR-004 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR-004 Volume 3: System Analysis. CNSNS-TR-004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR-004 Volume 5: Appendices A, B and C. This volume presents the results of the system analysis for the Laguna Verde Unit 1 Nuclear Power Plant. The system analysis involved the development of logical models for all the systems included in the accident sequence event tree headings, and for all the support systems required to operate the front line systems. For the Internal Event analysis for Laguna Verde, 16 front line systems and 5 support systems were included. Detailed fault trees were developed for most of the important systems. Simplified fault trees focusing on major faults were constructed for those systems that can be adequately represent,ed using this kind of modeling. For those systems where fault tree models were not constructed, actual data were used to represent the dominant failures of the systems. The main failures included in the fault trees are hardware failures, test and maintenance unavailabilities, common cause failures, and human errors. The SETS and TEMAC codes were used to perform the qualitative and quantitative fault tree analyses. (Author)

  16. Discussion of comments from a peer review of a technique for human event analysis (ATHEANA)

    International Nuclear Information System (INIS)

    Forester, J.A.; Ramey-Smith, A.; Bley, D.C.; Kolaczkowski, A.M.; Cooper, S.E.; Wreathall, J.

    1998-01-01

    In May of 1998, a technical basis and implementation guidelines document for A Technique for Human Event Analysis (ATHEANA) was issued as a draft report for public comment (NUREG-1624). In conjunction with the release of the draft NUREG, a paper review of the method, its documentation, and the results of an initial test of the method was held over a two-day period in Seattle, Washington, in June of 1998. Four internationally-known and respected experts in human reliability analysis (HRA) were selected to serve as the peer reviewers and were paid for their services. In addition, approximately 20 other individuals with an interest in HRA and ATHEANA also attended the peer review meeting and were invited to provide comments. The peer review team was asked to comment on any aspect of the method or the report in which improvements could be made and to discuss its strengths and weaknesses. All of the reviewers thought the ATEANA method had made significant contributions to the field of PRA/HRA, in particular by addressing the most important open questions and issues in HRA, by attempting to develop an integrated approach, and by developing a framework capable of identifying types of unsafe actions that generally have not been considered using existing methods. The reviewers had many concerns about specific aspects of the methodology and made many recommendations for ways to improve and extend the method, and to make its application more cost effective and useful to PRA in general. Details of the reviewers' comments and the ATHEANA team's responses to specific criticisms will be discussed

  17. Human reliability analysis for probabilistic safety assessments - review of methods and issues

    International Nuclear Information System (INIS)

    Srinivas, G.; Guptan, Rajee; Malhotra, P.K.; Ghadge, S.G.; Chandra, Umesh

    2011-01-01

    It is well known that the two major events in World Nuclear Power Plant Operating history, namely the Three Mile Island and Chernobyl, were Human failure events. Subsequent to these two events, several significant changes have been incorporated in Plant Design, Control Room Design and Operator Training to reduce the possibility of Human errors during plant transients. Still, human error contribution to Risk in Nuclear Power Plant operations has been a topic of continued attention for research, development and analysis. Probabilistic Safety Assessments attempt to capture all potential human errors with a scientifically computed failure probability, through Human Reliability Analysis. Several methods are followed by different countries to quantify the Human error probability. This paper reviews the various popular methods being followed, critically examines them with reference to their criticisms and brings out issues for future research. (author)

  18. Root cause analysis of relevant events

    International Nuclear Information System (INIS)

    Perez, Silvia S.; Vidal, Patricia G.

    2000-01-01

    During 1998 the research work followed more specific guidelines, which entailed focusing exclusively on the two selected methods (ASSET and HPIP) and incorporating some additional human behaviour elements based on the documents of reference. Once resident inspectors were incorporated in the project (and trained accordingly), events occurring in Argentine nuclear power plants were analysed. Some events were analysed (all of them from Atucha I and Embalse nuclear power plant), concluding that the systematic methodology used allows us to investigate also minor events that were precursors of the events selected. (author)

  19. Human Factors Reliability Analysis for Assuring Nuclear Safety Using Fuzzy Fault Tree

    International Nuclear Information System (INIS)

    Eisawy, E.A.-F. I.; Sallam, H.

    2016-01-01

    In order to ensure effective prevention of harmful events, the risk assessment process cannot ignore the role of humans in the dynamics of accidental events and thus the seriousness of the consequences that may derive from them. Human reliability analysis (HRA) involves the use of qualitative and quantitative methods to assess the human contribution to risk. HRA techniques have been developed in order to provide human error probability values associated with operators’ tasks to be included within the broader context of system risk assessment, and are aimed at reducing the probability of accidental events. Fault tree analysis (FTA) is a graphical model that displays the various combinations of equipment failures and human errors that can result in the main system failure of interest. FTA is a risk analysis technique to assess likelihood (in a probabilistic context) of an event. The objective data available to estimate the likelihood is often missing, and even if available, is subject to incompleteness and imprecision or vagueness. Without addressing incompleteness and imprecision in the available data, FTA and subsequent risk analysis give a false impression of precision and correctness that undermines the overall credibility of the process. To solve this problem, qualitative justification in the context of failure possibilities can be used as alternative for quantitative justification. In this paper, we introduce the approach of fuzzy reliability as solution for fault tree analysis drawbacks. A new fuzzy fault tree method is proposed for the analysis of human reliability based on fuzzy sets and fuzzy operations t-norms, co-norms, defuzzification, and fuzzy failure probability. (author)

  20. A technique for human error analysis (ATHEANA)

    International Nuclear Information System (INIS)

    Cooper, S.E.; Ramey-Smith, A.M.; Wreathall, J.; Parry, G.W.

    1996-05-01

    Probabilistic risk assessment (PRA) has become an important tool in the nuclear power industry, both for the Nuclear Regulatory Commission (NRC) and the operating utilities. Human reliability analysis (HRA) is a critical element of PRA; however, limitations in the analysis of human actions in PRAs have long been recognized as a constraint when using PRA. A multidisciplinary HRA framework has been developed with the objective of providing a structured approach for analyzing operating experience and understanding nuclear plant safety, human error, and the underlying factors that affect them. The concepts of the framework have matured into a rudimentary working HRA method. A trial application of the method has demonstrated that it is possible to identify potentially significant human failure events from actual operating experience which are not generally included in current PRAs, as well as to identify associated performance shaping factors and plant conditions that have an observable impact on the frequency of core damage. A general process was developed, albeit in preliminary form, that addresses the iterative steps of defining human failure events and estimating their probabilities using search schemes. Additionally, a knowledge- base was developed which describes the links between performance shaping factors and resulting unsafe actions

  1. A technique for human error analysis (ATHEANA)

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, S.E.; Ramey-Smith, A.M.; Wreathall, J.; Parry, G.W. [and others

    1996-05-01

    Probabilistic risk assessment (PRA) has become an important tool in the nuclear power industry, both for the Nuclear Regulatory Commission (NRC) and the operating utilities. Human reliability analysis (HRA) is a critical element of PRA; however, limitations in the analysis of human actions in PRAs have long been recognized as a constraint when using PRA. A multidisciplinary HRA framework has been developed with the objective of providing a structured approach for analyzing operating experience and understanding nuclear plant safety, human error, and the underlying factors that affect them. The concepts of the framework have matured into a rudimentary working HRA method. A trial application of the method has demonstrated that it is possible to identify potentially significant human failure events from actual operating experience which are not generally included in current PRAs, as well as to identify associated performance shaping factors and plant conditions that have an observable impact on the frequency of core damage. A general process was developed, albeit in preliminary form, that addresses the iterative steps of defining human failure events and estimating their probabilities using search schemes. Additionally, a knowledge- base was developed which describes the links between performance shaping factors and resulting unsafe actions.

  2. Human event observations in the individual plant examinations

    International Nuclear Information System (INIS)

    Lois, E.; Forester, J.

    1994-01-01

    A main objective of the Nuclear Regulatory Commission's (NRC) Individual Plant Examination (IPE) Insights Program is to document significant safety insights relative to core damage frequency (CDF) for the different reactor and containment types and plant designs as indicated in the IPEs. The Human Reliability Analysis (HRA) is a critical component of the Probabilistic Risk Assessments (PRAs) which were done for the IPEs. The determination and selection of human actions for incorporation into the event and fault tree models and the quantification of their failure probabilities can have an important impact on the resulting estimates of CDF and risk. Therefore, two important goals of the NRCs IPE Insights Program are (1) to determine the extent to which human actions and their corresponding failure probabilities influenced the results of the IPEs and (2) to identify which factors played significant roles in determining the differences and similarities in the results of the HRA analyses across the different plants. To obtain the relevant information, the NRCs IPE database, which contains information on plant design, CDF, and containment performance obtained from the IPEs, was used in conjunction with a systematic examination of the HRA results from the IPEs

  3. Bayesian analysis of rare events

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Daniel, E-mail: straub@tum.de; Papaioannou, Iason; Betz, Wolfgang

    2016-06-01

    In many areas of engineering and science there is an interest in predicting the probability of rare events, in particular in applications related to safety and security. Increasingly, such predictions are made through computer models of physical systems in an uncertainty quantification framework. Additionally, with advances in IT, monitoring and sensor technology, an increasing amount of data on the performance of the systems is collected. This data can be used to reduce uncertainty, improve the probability estimates and consequently enhance the management of rare events and associated risks. Bayesian analysis is the ideal method to include the data into the probabilistic model. It ensures a consistent probabilistic treatment of uncertainty, which is central in the prediction of rare events, where extrapolation from the domain of observation is common. We present a framework for performing Bayesian updating of rare event probabilities, termed BUS. It is based on a reinterpretation of the classical rejection-sampling approach to Bayesian analysis, which enables the use of established methods for estimating probabilities of rare events. By drawing upon these methods, the framework makes use of their computational efficiency. These methods include the First-Order Reliability Method (FORM), tailored importance sampling (IS) methods and Subset Simulation (SuS). In this contribution, we briefly review these methods in the context of the BUS framework and investigate their applicability to Bayesian analysis of rare events in different settings. We find that, for some applications, FORM can be highly efficient and is surprisingly accurate, enabling Bayesian analysis of rare events with just a few model evaluations. In a general setting, BUS implemented through IS and SuS is more robust and flexible.

  4. Alternative splicing events identified in human embryonic stem cells and neural progenitors.

    Directory of Open Access Journals (Sweden)

    Gene W Yeo

    2007-10-01

    Full Text Available Human embryonic stem cells (hESCs and neural progenitor (NP cells are excellent models for recapitulating early neuronal development in vitro, and are key to establishing strategies for the treatment of degenerative disorders. While much effort had been undertaken to analyze transcriptional and epigenetic differences during the transition of hESC to NP, very little work has been performed to understand post-transcriptional changes during neuronal differentiation. Alternative RNA splicing (AS, a major form of post-transcriptional gene regulation, is important in mammalian development and neuronal function. Human ESC, hESC-derived NP, and human central nervous system stem cells were compared using Affymetrix exon arrays. We introduced an outlier detection approach, REAP (Regression-based Exon Array Protocol, to identify 1,737 internal exons that are predicted to undergo AS in NP compared to hESC. Experimental validation of REAP-predicted AS events indicated a threshold-dependent sensitivity ranging from 56% to 69%, at a specificity of 77% to 96%. REAP predictions significantly overlapped sets of alternative events identified using expressed sequence tags and evolutionarily conserved AS events. Our results also reveal that focusing on differentially expressed genes between hESC and NP will overlook 14% of potential AS genes. In addition, we found that REAP predictions are enriched in genes encoding serine/threonine kinase and helicase activities. An example is a REAP-predicted alternative exon in the SLK (serine/threonine kinase 2 gene that is differentially included in hESC, but skipped in NP as well as in other differentiated tissues. Lastly, comparative sequence analysis revealed conserved intronic cis-regulatory elements such as the FOX1/2 binding site GCAUG as being proximal to candidate AS exons, suggesting that FOX1/2 may participate in the regulation of AS in NP and hESC. In summary, a new methodology for exon array analysis was introduced

  5. Human Error Assessmentin Minefield Cleaning Operation Using Human Event Analysis

    Directory of Open Access Journals (Sweden)

    Mohammad Hajiakbari

    2015-12-01

    Full Text Available Background & objective: Human error is one of the main causes of accidents. Due to the unreliability of the human element and the high-risk nature of demining operations, this study aimed to assess and manage human errors likely to occur in such operations. Methods: This study was performed at a demining site in war zones located in the West of Iran. After acquiring an initial familiarity with the operations, methods, and tools of clearing minefields, job task related to clearing landmines were specified. Next, these tasks were studied using HTA and related possible errors were assessed using ATHEANA. Results: de-mining task was composed of four main operations, including primary detection, technical identification, investigation, and neutralization. There were found four main reasons for accidents occurring in such operations; walking on the mines, leaving mines with no action, error in neutralizing operation and environmental explosion. The possibility of human error in mine clearance operations was calculated as 0.010. Conclusion: The main causes of human error in de-mining operations can be attributed to various factors such as poor weather and operating conditions like outdoor work, inappropriate personal protective equipment, personality characteristics, insufficient accuracy in the work, and insufficient time available. To reduce the probability of human error in de-mining operations, the aforementioned factors should be managed properly.

  6. DEPEND-HRA-A method for consideration of dependency in human reliability analysis

    International Nuclear Information System (INIS)

    Cepin, Marko

    2008-01-01

    A consideration of dependencies between human actions is an important issue within the human reliability analysis. A method was developed, which integrates the features of existing methods and the experience from a full scope plant simulator. The method is used on real plant-specific human reliability analysis as a part of the probabilistic safety assessment of a nuclear power plant. The method distinguishes dependency for pre-initiator events from dependency for initiator and post-initiator events. The method identifies dependencies based on scenarios, where consecutive human actions are modeled, and based on a list of minimal cut sets, which is obtained by running the minimal cut set analysis considering high values of human error probabilities in the evaluation. A large example study, which consisted of a large number of human failure events, demonstrated the applicability of the method. Comparative analyses that were performed show that both selection of dependency method and selection of dependency levels within the method largely impact the results of probabilistic safety assessment. If the core damage frequency is not impacted much, the listings of important basic events in terms of risk increase and risk decrease factors may change considerably. More efforts are needed on the subject, which will prepare the background for more detailed guidelines, which will remove the subjectivity from the evaluations as much as it is possible

  7. Classification system for reporting events involving human malfunctions

    DEFF Research Database (Denmark)

    Rasmussen, Jens; Pedersen, O.M.; Mancini, G.

    1981-01-01

    The report describes a set of categories for reporting indus-trial incidents and events involving human malfunction. The classification system aims at ensuring information adequate for improvement of human work situations and man-machine interface systems and for attempts to quantify "human error......" rates. The classification system has a multifacetted non-hierarchical struc-ture and its compatibility with Isprals ERDS classification is described. The collection of the information in general and for quantification purposes are discussed. 24 categories, 12 of which being human factors oriented......, are listed with their respective subcategories, and comments are given. Underlying models of human data processes and their typical malfunc-tions and of a human decision sequence are described....

  8. Classification system for reporting events involving human malfunctions

    International Nuclear Information System (INIS)

    Rasmussen, J.; Pedersen, O.M.; Mancini, G.; Carnino, A.; Griffon, M.; Gagnolet, P.

    1981-03-01

    The report describes a set of categories for reporting industrial incidents and events involving human malfunction. The classification system aims at ensuring information adequate for improvement of human work situations and man-machine interface systems and for attempts to quantify ''human error'' rates. The classification system has a multifacetted non-hierarchial structure and its compatibility with Ispra's ERDS classification is described. The collection of the information in general and for quantification purposes are discussed. 24 categories, 12 of which being human factors oriented, are listed with their respective subcategories, and comments are given. Underlying models of human data processes and their typical malfunctions and of a human decision sequence are described. (author)

  9. External event analysis methods for NUREG-1150

    International Nuclear Information System (INIS)

    Bohn, M.P.; Lambright, J.A.

    1989-01-01

    The US Nuclear Regulatory Commission is sponsoring probabilistic risk assessments of six operating commercial nuclear power plants as part of a major update of the understanding of risk as provided by the original WASH-1400 risk assessments. In contrast to the WASH-1400 studies, at least two of the NUREG-1150 risk assessments will include an analysis of risks due to earthquakes, fires, floods, etc., which are collectively known as eternal events. This paper summarizes the methods to be used in the external event analysis for NUREG-1150 and the results obtained to date. The two plants for which external events are being considered are Surry and Peach Bottom, a PWR and BWR respectively. The external event analyses (through core damage frequency calculations) were completed in June 1989, with final documentation available in September. In contrast to most past external event analyses, wherein rudimentary systems models were developed reflecting each external event under consideration, the simplified NUREG-1150 analyses are based on the availability of the full internal event PRA systems models (event trees and fault trees) and make use of extensive computer-aided screening to reduce them to sequence cut sets important to each external event. This provides two major advantages in that consistency and scrutability with respect to the internal event analysis is achieved, and the full gamut of random and test/maintenance unavailabilities are automatically included, while only those probabilistically important survive the screening process. Thus, full benefit of the internal event analysis is obtained by performing the internal and external event analyses sequentially

  10. Human Reliability Assessment and Human Performance Evaluation: Research and Analysis Activities at the U.S. NRC

    International Nuclear Information System (INIS)

    Ramey-Smith, A.M.

    1998-01-01

    The author indicates the themes of the six programs identified by the US NRC mission on human performance and human reliability activities. They aim at developing the technical basis to support human performance, at developing and updating a model of human performance and human reliability, at fostering national and international dialogue and cooperation efforts on human performance evaluation, at conducting operating events analysis and database development, and at providing support to human performance and human reliability inspection

  11. Collecting operational event data for statistical analysis

    International Nuclear Information System (INIS)

    Atwood, C.L.

    1994-09-01

    This report gives guidance for collecting operational data to be used for statistical analysis, especially analysis of event counts. It discusses how to define the purpose of the study, the unit (system, component, etc.) to be studied, events to be counted, and demand or exposure time. Examples are given of classification systems for events in the data sources. A checklist summarizes the essential steps in data collection for statistical analysis

  12. Gait Event Detection in Real-World Environment for Long-Term Applications: Incorporating Domain Knowledge Into Time-Frequency Analysis.

    Science.gov (United States)

    Khandelwal, Siddhartha; Wickstrom, Nicholas

    2016-12-01

    Detecting gait events is the key to many gait analysis applications that would benefit from continuous monitoring or long-term analysis. Most gait event detection algorithms using wearable sensors that offer a potential for use in daily living have been developed from data collected in controlled indoor experiments. However, for real-word applications, it is essential that the analysis is carried out in humans' natural environment; that involves different gait speeds, changing walking terrains, varying surface inclinations and regular turns among other factors. Existing domain knowledge in the form of principles or underlying fundamental gait relationships can be utilized to drive and support the data analysis in order to develop robust algorithms that can tackle real-world challenges in gait analysis. This paper presents a novel approach that exhibits how domain knowledge about human gait can be incorporated into time-frequency analysis to detect gait events from long-term accelerometer signals. The accuracy and robustness of the proposed algorithm are validated by experiments done in indoor and outdoor environments with approximately 93 600 gait events in total. The proposed algorithm exhibits consistently high performance scores across all datasets in both, indoor and outdoor environments.

  13. Initiating Event Analysis of a Lithium Fluoride Thorium Reactor

    Science.gov (United States)

    Geraci, Nicholas Charles

    The primary purpose of this study is to perform an Initiating Event Analysis for a Lithium Fluoride Thorium Reactor (LFTR) as the first step of a Probabilistic Safety Assessment (PSA). The major objective of the research is to compile a list of key initiating events capable of resulting in failure of safety systems and release of radioactive material from the LFTR. Due to the complex interactions between engineering design, component reliability and human reliability, probabilistic safety assessments are most useful when the scope is limited to a single reactor plant. Thus, this thesis will study the LFTR design proposed by Flibe Energy. An October 2015 Electric Power Research Institute report on the Flibe Energy LFTR asked "what-if?" questions of subject matter experts and compiled a list of key hazards with the most significant consequences to the safety or integrity of the LFTR. The potential exists for unforeseen hazards to pose additional risk for the LFTR, but the scope of this thesis is limited to evaluation of those key hazards already identified by Flibe Energy. These key hazards are the starting point for the Initiating Event Analysis performed in this thesis. Engineering evaluation and technical study of the plant using a literature review and comparison to reference technology revealed four hazards with high potential to cause reactor core damage. To determine the initiating events resulting in realization of these four hazards, reference was made to previous PSAs and existing NRC and EPRI initiating event lists. Finally, fault tree and event tree analyses were conducted, completing the logical classification of initiating events. Results are qualitative as opposed to quantitative due to the early stages of system design descriptions and lack of operating experience or data for the LFTR. In summary, this thesis analyzes initiating events using previous research and inductive and deductive reasoning through traditional risk management techniques to

  14. Changes in extreme events and the potential impacts on human health.

    Science.gov (United States)

    Bell, Jesse E; Brown, Claudia Langford; Conlon, Kathryn; Herring, Stephanie; Kunkel, Kenneth E; Lawrimore, Jay; Luber, George; Schreck, Carl; Smith, Adam; Uejio, Christopher

    2018-04-01

    Extreme weather and climate-related events affect human health by causing death, injury, and illness, as well as having large socioeconomic impacts. Climate change has caused changes in extreme event frequency, intensity, and geographic distribution, and will continue to be a driver for change in the future. Some of these events include heat waves, droughts, wildfires, dust storms, flooding rains, coastal flooding, storm surges, and hurricanes. The pathways connecting extreme events to health outcomes and economic losses can be diverse and complex. The difficulty in predicting these relationships comes from the local societal and environmental factors that affect disease burden. More information is needed about the impacts of climate change on public health and economies to effectively plan for and adapt to climate change. This paper describes some of the ways extreme events are changing and provides examples of the potential impacts on human health and infrastructure. It also identifies key research gaps to be addressed to improve the resilience of public health to extreme events in the future. Extreme weather and climate events affect human health by causing death, injury, and illness, as well as having large socioeconomic impacts. Climate change has caused changes in extreme event frequency, intensity, and geographic distribution, and will continue to be a driver for change in the future. Some of these events include heat waves, droughts, wildfires, flooding rains, coastal flooding, surges, and hurricanes. The pathways connecting extreme events to health outcomes and economic losses can be diverse and complex. The difficulty in predicting these relationships comes from the local societal and environmental factors that affect disease burden.

  15. EVENT PLANNING USING FUNCTION ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    Lori Braase; Jodi Grgich

    2011-06-01

    Event planning is expensive and resource intensive. Function analysis provides a solid foundation for comprehensive event planning (e.g., workshops, conferences, symposiums, or meetings). It has been used at Idaho National Laboratory (INL) to successfully plan events and capture lessons learned, and played a significant role in the development and implementation of the “INL Guide for Hosting an Event.” Using a guide and a functional approach to planning utilizes resources more efficiently and reduces errors that could be distracting or detrimental to an event. This integrated approach to logistics and program planning – with the primary focus on the participant – gives us the edge.

  16. Phoenix – A model-based Human Reliability Analysis methodology: Qualitative Analysis Procedure

    International Nuclear Information System (INIS)

    Ekanem, Nsimah J.; Mosleh, Ali; Shen, Song-Hua

    2016-01-01

    Phoenix method is an attempt to address various issues in the field of Human Reliability Analysis (HRA). Built on a cognitive human response model, Phoenix incorporates strong elements of current HRA good practices, leverages lessons learned from empirical studies, and takes advantage of the best features of existing and emerging HRA methods. Its original framework was introduced in previous publications. This paper reports on the completed methodology, summarizing the steps and techniques of its qualitative analysis phase. The methodology introduces the “Crew Response Tree” which provides a structure for capturing the context associated with Human Failure Events (HFEs), including errors of omission and commission. It also uses a team-centered version of the Information, Decision and Action cognitive model and “macro-cognitive” abstractions of crew behavior, as well as relevant findings from cognitive psychology literature and operating experience, to identify potential causes of failures and influencing factors during procedure-driven and knowledge-supported crew-plant interactions. The result is the set of identified HFEs and likely scenarios leading to each. The methodology itself is generic in the sense that it is compatible with various quantification methods, and can be adapted for use across different environments including nuclear, oil and gas, aerospace, aviation, and healthcare. - Highlights: • Produces a detailed, consistent, traceable, reproducible and properly documented HRA. • Uses “Crew Response Tree” to capture context associated with Human Failure Events. • Models dependencies between Human Failure Events and influencing factors. • Provides a human performance model for relating context to performance. • Provides a framework for relating Crew Failure Modes to its influencing factors.

  17. Human reliability analysis of control room operators

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Isaac J.A.L.; Carvalho, Paulo Victor R.; Grecco, Claudio H.S. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)

    2005-07-01

    Human reliability is the probability that a person correctly performs some system required action in a required time period and performs no extraneous action that can degrade the system Human reliability analysis (HRA) is the analysis, prediction and evaluation of work-oriented human performance using some indices as human error likelihood and probability of task accomplishment. Significant progress has been made in the HRA field during the last years, mainly in nuclear area. Some first-generation HRA methods were developed, as THERP (Technique for human error rate prediction). Now, an array of called second-generation methods are emerging as alternatives, for instance ATHEANA (A Technique for human event analysis). The ergonomics approach has as tool the ergonomic work analysis. It focus on the study of operator's activities in physical and mental form, considering at the same time the observed characteristics of operator and the elements of the work environment as they are presented to and perceived by the operators. The aim of this paper is to propose a methodology to analyze the human reliability of the operators of industrial plant control room, using a framework that includes the approach used by ATHEANA, THERP and the work ergonomics analysis. (author)

  18. Post-event human decision errors: operator action tree/time reliability correlation

    International Nuclear Information System (INIS)

    Hall, R.E.; Fragola, J.; Wreathall, J.

    1982-11-01

    This report documents an interim framework for the quantification of the probability of errors of decision on the part of nuclear power plant operators after the initiation of an accident. The framework can easily be incorporated into an event tree/fault tree analysis. The method presented consists of a structure called the operator action tree and a time reliability correlation which assumes the time available for making a decision to be the dominating factor in situations requiring cognitive human response. This limited approach decreases the magnitude and complexity of the decision modeling task. Specifically, in the past, some human performance models have attempted prediction by trying to emulate sequences of human actions, or by identifying and modeling the information processing approach applicable to the task. The model developed here is directed at describing the statistical performance of a representative group of hypothetical individuals responding to generalized situations

  19. Post-event human decision errors: operator action tree/time reliability correlation

    Energy Technology Data Exchange (ETDEWEB)

    Hall, R E; Fragola, J; Wreathall, J

    1982-11-01

    This report documents an interim framework for the quantification of the probability of errors of decision on the part of nuclear power plant operators after the initiation of an accident. The framework can easily be incorporated into an event tree/fault tree analysis. The method presented consists of a structure called the operator action tree and a time reliability correlation which assumes the time available for making a decision to be the dominating factor in situations requiring cognitive human response. This limited approach decreases the magnitude and complexity of the decision modeling task. Specifically, in the past, some human performance models have attempted prediction by trying to emulate sequences of human actions, or by identifying and modeling the information processing approach applicable to the task. The model developed here is directed at describing the statistical performance of a representative group of hypothetical individuals responding to generalized situations.

  20. Classification system for reporting events involving human malfunctions

    International Nuclear Information System (INIS)

    Rasmussen, J.; Pedersen, O.M.; Mancini, G.

    1981-01-01

    The report describes a set of categories for reporting industrial incidents and events involving human malfunction. The classification system aims at ensuring information adequate for improvement of human work situations and man-machine interface systems and for attempts to quantify ''human error'' rates. The classification system has a multifacetted non-hierarchical structure and its compatibility with Ispra's ERDS classification is described. The collection of the information in general and for quantification purposes are discussed. 24 categories, 12 of which being human factors-oriented, are listed with their respective subcategories, and comments are given. Underlying models of human data process and their typical malfuntions and of a human decision sequence are described. The work reported is a joint contribution to the CSNI Group of Experts on Human Error Data and Assessment

  1. Quantification results from an application of a new technique for human event analysis (ATHEANA) at a pressurized water reactor

    International Nuclear Information System (INIS)

    Whitehead, D.W.; Kolaczkowski, A.M.; Thompson, C.M.

    1998-05-01

    This paper presents results from the quantification of the three human failure events (HFEs) identified using the ATHEANA methodology as discussed in an earlier companion paper presented at this conference. Sections describe the quantification task, important basic events, and the results obtained from quantifying the three HFEs that were identified -- the first two of which were simulated at the Seabrook Station Simulator

  2. Task Decomposition in Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Boring, Ronald Laurids [Idaho National Laboratory; Joe, Jeffrey Clark [Idaho National Laboratory

    2014-06-01

    In the probabilistic safety assessments (PSAs) used in the nuclear industry, human failure events (HFEs) are determined as a subset of hardware failures, namely those hardware failures that could be triggered by human action or inaction. This approach is top-down, starting with hardware faults and deducing human contributions to those faults. Elsewhere, more traditionally human factors driven approaches would tend to look at opportunities for human errors first in a task analysis and then identify which of those errors is risk significant. The intersection of top-down and bottom-up approaches to defining HFEs has not been carefully studied. Ideally, both approaches should arrive at the same set of HFEs. This question remains central as human reliability analysis (HRA) methods are generalized to new domains like oil and gas. The HFEs used in nuclear PSAs tend to be top-down— defined as a subset of the PSA—whereas the HFEs used in petroleum quantitative risk assessments (QRAs) are more likely to be bottom-up—derived from a task analysis conducted by human factors experts. The marriage of these approaches is necessary in order to ensure that HRA methods developed for top-down HFEs are also sufficient for bottom-up applications.

  3. An investigation on unintended reactor trip events in terms of human error hazards of Korean nuclear power plants

    International Nuclear Information System (INIS)

    Kim, Sa Kil; Lee, Yong Hee; Jang, Tong Il; Oh, Yeon Ju; Shin, Kwang Hyeon

    2014-01-01

    Highlights: • A methodology to identify human error hazards has been established. • The proposed methodology is a preventive approach to identify not only human error causes but also its hazards. • Using the HFACS framework we tried to find out not causations but all of the hazards and relationships among them. • We determined countermeasures against human errors through dealing with latent factors such as organizational influences. - Abstract: A new approach for finding the hazards of human errors, and not just their causes, in the nuclear industry is currently required. This is because finding causes of human errors is really impossible owing to the multiplicity of causes in each case. Thus, this study aims at identifying the relationships among human error hazards and determining the strategies for preventing human error events by means of a reanalysis of the reactor trip events in Korea NPPs. We investigated human errors to find latent factors such as decisions and conditions in all of the unintended reactor trip events during the last dozen years. In this study, we applied the HFACS (Human Factors Analysis and Classification System), which is a commonly utilized tool for investigating human contributions to aviation accidents under a widespread evaluation scheme. Using the HFACS framework, we tried to find out not the causations but all of the hazards and their relationships in terms of organizational factors. Through the trial, we proposed not only meaningful frequencies of each hazards also correlations of them. Also, considering the correlations of each hazards, we suggested useful strategies to prevent human error event. A method to investigate unintended nuclear reactor trips by human errors and the results will be discussed in more detail

  4. Analysis of Loss-of-Offsite-Power Events 1997-2015

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Nancy Ellen [Idaho National Lab. (INL), Idaho Falls, ID (United States); Schroeder, John Alton [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-07-01

    Loss of offsite power (LOOP) can have a major negative impact on a power plant’s ability to achieve and maintain safe shutdown conditions. LOOP event frequencies and times required for subsequent restoration of offsite power are important inputs to plant probabilistic risk assessments. This report presents a statistical and engineering analysis of LOOP frequencies and durations at U.S. commercial nuclear power plants. The data used in this study are based on the operating experience during calendar years 1997 through 2015. LOOP events during critical operation that do not result in a reactor trip, are not included. Frequencies and durations were determined for four event categories: plant-centered, switchyard-centered, grid-related, and weather-related. Emergency diesel generator reliability is also considered (failure to start, failure to load and run, and failure to run more than 1 hour). There is an adverse trend in LOOP durations. The previously reported adverse trend in LOOP frequency was not statistically significant for 2006-2015. Grid-related LOOPs happen predominantly in the summer. Switchyard-centered LOOPs happen predominantly in winter and spring. Plant-centered and weather-related LOOPs do not show statistically significant seasonality. The engineering analysis of LOOP data shows that human errors have been much less frequent since 1997 than in the 1986 -1996 time period.

  5. Whole genome analysis of selected human and animal rotaviruses identified in Uganda from 2012 to 2014 reveals complex genome reassortment events between human, bovine, caprine and porcine strains.

    Science.gov (United States)

    Bwogi, Josephine; Jere, Khuzwayo C; Karamagi, Charles; Byarugaba, Denis K; Namuwulya, Prossy; Baliraine, Frederick N; Desselberger, Ulrich; Iturriza-Gomara, Miren

    2017-01-01

    Rotaviruses of species A (RVA) are a common cause of diarrhoea in children and the young of various other mammals and birds worldwide. To investigate possible interspecies transmission of RVAs, whole genomes of 18 human and 6 domestic animal RVA strains identified in Uganda between 2012 and 2014 were sequenced using the Illumina HiSeq platform. The backbone of the human RVA strains had either a Wa- or a DS-1-like genetic constellation. One human strain was a Wa-like mono-reassortant containing a DS-1-like VP2 gene of possible animal origin. All eleven genes of one bovine RVA strain were closely related to those of human RVAs. One caprine strain had a mixed genotype backbone, suggesting that it emerged from multiple reassortment events involving different host species. The porcine RVA strains had mixed genotype backbones with possible multiple reassortant events with strains of human and bovine origin.Overall, whole genome characterisation of rotaviruses found in domestic animals in Uganda strongly suggested the presence of human-to animal RVA transmission, with concomitant circulation of multi-reassortant strains potentially derived from complex interspecies transmission events. However, whole genome data from the human RVA strains causing moderate and severe diarrhoea in under-fives in Uganda indicated that they were primarily transmitted from person-to-person.

  6. Human reliability analysis for steam generator feed-and-bleed accident in Bushehr NPP-1

    International Nuclear Information System (INIS)

    Jafarian, Reza; Sepanloo, Kamran

    2006-01-01

    According to the incident/accident reports, unsuccessful implementation of steam generator feed-and-bleed procedure is one of the most important events in nuclear power plants operation which greatly contributes to the level of risk of the plants. Generally, the loss of all feed water pumps flow (as one of the precursors) results in failure to maintain adequate cooling of the reactor core unless the operating crew initiate and follow the feed-and-bleed procedure correctly and timely. In this paper, firstly, a Human Reliability Analysis (HRA) event tree is presented delineating the major human activities and errors in the implementation of the steam generator (SG) feed-and-bleed procedure following the loss of (both normal and emergency) water feed to four SGs of Bushehr Nuclear Power Plant Unit 1 (BNPP-1). Secondly, the graphical method of task analysis as a part of HRA is used as a means of delineating correct and incorrect human actions. To be used in the probabilistic risk assessment (PRA), the outputs of the HRA event trees are fed into the system event trees, functional event trees or system fault trees. As a part of a probabilistic risk assessment of BNPP-1 and to assess the reliability of control room operators, a human reliability analysis model is applied based on the THERP (Technique for Human Error Rate Prediction) technique. The THERP method is used in the form of event trees named as the probability tree diagrams. In this research the Human Reliability Analysis event tree is constructed based on the background information and assumptions made and on a similar NPP task analysis. It is done so because the BNPP-1 is not an operational nuclear power plant. Thirdly, based on NUREG/CR-1278 Handbook, a computer program has been developed in Visual Basic language and used to illustrate the major human activities and determination of error rates of operators in the course of the implementation of the steam generator feed-and-bleed procedure. Finally, total

  7. Human Reliability Analysis for steam generator feed-and-bleed accident in Bushehr NPP-1

    International Nuclear Information System (INIS)

    Jafarian, R.; Sepanloo, K.

    2005-01-01

    According to the incident/accident reports, unsuccessful implementation of steam generator feed-and-bleed procedure is one of the most important events in nuclear power plants operation which greatly contributes to the level of risk of the plants. Generally, the loss of all feed water pumps flow (as one of the precursors) results in failure to maintain adequate cooling of the reactor core unless the operating crew initiate and follow the feed-and-bleed procedure correctly and timely. In this paper, firstly, a Human Reliability Analysis (HRA) event tree is presented delineating the major human activities and errors in the implementation of the steam generator (SG) feed-and-bleed procedure following the loss of (both normal and emergency) water feed to four SGs of Bushehr Nuclear Power Plant unit1 (BNPP-1). Secondly, the graphical method of task analysis as a part of HRA is used as a means of delineating correct and incorrect human actions. To be used in the probabilistic risk assessment (PRA), the outputs of the HRA event trees are fed into the system event trees, functional event trees or system fault trees. As a part of a probabilistic risk assessment of BNPP-1 and to assess the reliability of control room operators, a human reliability analysis model is applied based on the THERP (Technique for Human Error Rate Prediction) technique. The THERP method is used in the form of event trees named as the probability tree diagrams. In this research the Human Reliability Analysis event tree is constructed based on the background information and assumptions made and on a similar NPP task analysis. It is done so because the BNPP-1 is not an operational nuclear power plant. Thirdly, based on NUREG/CR-1278 Handbook, a computer program has been developed in Visual Basic language and used to illustrate the major human activities and determination of error rates of operators in the course of the implementation of the steam generator feed-and-bleed procedure. Finally, total

  8. Hybrid instrument applied to human reliability study in event of loss of external electric power in a nuclear power plant

    International Nuclear Information System (INIS)

    Martins, Eduardo Ferraz

    2015-01-01

    The study projects in highly complex installations involves robust modeling, supported by conceptual and mathematical tools, to carry out systematic research and structured the different risk scenarios that can lead to unwanted events from occurring equipment failures or human errors. In the context of classical modeling, the Probabilistic Safety Analysis (PSA) seeks to provide qualitative and quantitative information about the project particularity and their operational facilities, including the identification of factors or scenarios that contribute to the risk and consequent comparison options for increasing safety. In this context, the aim of the thesis is to develop a hybrid instrument (CPP-HI) innovative, from the integrated modeling techniques of Failure Mode and Effect Analysis (FMEA), concepts of Human Reliability Analysis and Probabilistic Composition of Preferences (PCP). In support of modeling and validation of the CPP-HI, a simulation was performed on a triggering event 'Loss of External Electric Power' - PEEE, in a Nuclear Power plant. The results were simulated in a virtual environment (sensitivity analysis) and are robust to the study of Human Reliability Analysis (HRA) in the context of the PSA. (author)

  9. Investigating cardiorespiratory interaction by cross-spectral analysis of event series

    Science.gov (United States)

    Schäfer, Carsten; Rosenblum, Michael G.; Pikovsky, Arkady S.; Kurths, Jürgen

    2000-02-01

    The human cardiovascular and respiratory systems interact with each other and show effects of modulation and synchronization. Here we present a cross-spectral technique that specifically considers the event-like character of the heartbeat and avoids typical restrictions of other spectral methods. Using models as well as experimental data, we demonstrate how modulation and synchronization can be distinguished. Finally, we compare the method to traditional techniques and to the analysis of instantaneous phases.

  10. Exploring the Human Ecology of the Younger Dryas Extraterrestrial Impact Event

    Science.gov (United States)

    Kennett, D. J.; Erlandson, J. M.; Braje, T. J.; Culleton, B. J.

    2007-05-01

    Several lines of evidence now exist for a major extraterrestrial impact event in North America at 12.9 ka (the YDB). This impact partially destabilized the Laurentide and Cordilleran ice sheets, triggered abrupt Younger Dryas cooling and extensive wildfires, and contributed to megafaunal extinction. This event also occurred soon after the well established colonization of the Americas by anatomically modern humans. Confirmation of this event would represent the first near-time extraterrestrial impact with significant effects on human populations. These likely included widespread, abrupt human mortality, population displacement, migration into less effected or newly established habitats, loss of cultural traditions, and resource diversification in the face of the massive megafaunal extinction and population reductions in surviving animal populations. Ultimately, these transformations established the context for the special character of plant and animal domestication and the emergence of agricultural economies in North America. We explore the Late Pleistocene archaeological record in North America within the context of documented major biotic changes associated with the YDB in North America and of the massive ecological affects hypothesized for this event.

  11. Preliminary safety analysis of unscrammed events for KLFR

    International Nuclear Information System (INIS)

    Kim, S.J.; Ha, G.S.

    2005-01-01

    The report presents the design features of KLFR; Safety Analysis Code; steady-state calculation results and analysis results of unscrammed events. The calculations of the steady-state and unscrammed events have been performed for the conceptual design of KLFR using SSC-K code. UTOP event results in no fuel damage and no centre-line melting. The inherent safety features are demonstrated through the analysis of ULOHS event. Although the analysis of ULOF has much uncertainties in the pump design, the analysis results show the inherent safety characteristics. 6% flow of rated flow of natural circulation is formed in the case of ULOF. In the metallic fuel rod, the cladding temperature is somewhat high due to the low heat transfer coefficient of lead. ULOHS event should be considered in design of RVACS for long-term cooling

  12. Analysis of Human Errors in Japanese Nuclear Power Plants using JHPES/JAESS

    International Nuclear Information System (INIS)

    Kojima, Mitsuhiro; Mimura, Masahiro; Yamaguchi, Osamu

    1998-01-01

    CRIEPI (Central Research Institute for Electric Power Industries) / HFC (Human Factors research Center) developed J-HPES (Japanese version of Human Performance Enhancement System) based on the HPES which was originally developed by INPO to analyze events resulted from human errors. J-HPES was systematized into a computer program named JAESS (J-HPES Analysis and Evaluation Support System) and both systems were distributed to all Japanese electric power companies to analyze events by themselves. CRIEPI / HFC also analyzed the incidents in Japanese nuclear power plants (NPPs) which were officially reported and identified as human error related with J-HPES / JAESS. These incidents have numbered up to 188 cases over the last 30 years. An outline of this analysis is given, and some preliminary findings are shown. (authors)

  13. Analysis of external events - Nuclear Power Plant Dukovany

    International Nuclear Information System (INIS)

    Hladky, Milan

    2000-01-01

    PSA of external events at level 1 covers internal events, floods, fires, other external events are not included yet. Shutdown PSA takes into account internal events, floods, fires, heavy load drop, other external events are not included yet. Final safety analysis report was conducted after 10 years of operation for all Dukovany operational units. Probabilistic approach was used for analysis of aircraft drop and external man-induced events. The risk caused by man-induced events was found to be negligible and was accepted by State Office for Nuclear Safety (SONS)

  14. Software failure events derivation and analysis by frame-based technique

    International Nuclear Information System (INIS)

    Huang, H.-W.; Shih, C.; Yih, Swu; Chen, M.-H.

    2007-01-01

    A frame-based technique, including physical frame, logical frame, and cognitive frame, was adopted to perform digital I and C failure events derivation and analysis for generic ABWR. The physical frame was structured with a modified PCTran-ABWR plant simulation code, which was extended and enhanced on the feedwater system, recirculation system, and steam line system. The logical model is structured with MATLAB, which was incorporated into PCTran-ABWR to improve the pressure control system, feedwater control system, recirculation control system, and automated power regulation control system. As a result, the software failure of these digital control systems can be properly simulated and analyzed. The cognitive frame was simulated by the operator awareness status in the scenarios. Moreover, via an internal characteristics tuning technique, the modified PCTran-ABWR can precisely reflect the characteristics of the power-core flow. Hence, in addition to the transient plots, the analysis results can then be demonstrated on the power-core flow map. A number of postulated I and C system software failure events were derived to achieve the dynamic analyses. The basis for event derivation includes the published classification for software anomalies, the digital I and C design data for ABWR, chapter 15 accident analysis of generic SAR, and the reported NPP I and C software failure events. The case study of this research includes: (1) the software CMF analysis for the major digital control systems; and (2) postulated ABWR digital I and C software failure events derivation from the actual happening of non-ABWR digital I and C software failure events, which were reported to LER of USNRC or IRS of IAEA. These events were analyzed by PCTran-ABWR. Conflicts among plant status, computer status, and human cognitive status are successfully identified. The operator might not easily recognize the abnormal condition, because the computer status seems to progress normally. However, a well

  15. Human reliability analysis of Lingao Nuclear Power Station

    International Nuclear Information System (INIS)

    Zhang Li; Huang Shudong; Yang Hong; He Aiwu; Huang Xiangrui; Zheng Tao; Su Shengbing; Xi Haiying

    2001-01-01

    The necessity of human reliability analysis (HRA) of Lingao Nuclear Power Station are analyzed, and the method and operation procedures of HRA is briefed. One of the human factors events (HFE) is analyzed in detail and some questions of HRA are discussed. The authors present the analytical results of 61 HFEs, and make a brief introduction of HRA contribution to Lingao Nuclear Power Station

  16. Research on Visual Analysis Methods of Terrorism Events

    Science.gov (United States)

    Guo, Wenyue; Liu, Haiyan; Yu, Anzhu; Li, Jing

    2016-06-01

    Under the situation that terrorism events occur more and more frequency throughout the world, improving the response capability of social security incidents has become an important aspect to test governments govern ability. Visual analysis has become an important method of event analysing for its advantage of intuitive and effective. To analyse events' spatio-temporal distribution characteristics, correlations among event items and the development trend, terrorism event's spatio-temporal characteristics are discussed. Suitable event data table structure based on "5W" theory is designed. Then, six types of visual analysis are purposed, and how to use thematic map and statistical charts to realize visual analysis on terrorism events is studied. Finally, experiments have been carried out by using the data provided by Global Terrorism Database, and the results of experiments proves the availability of the methods.

  17. Risk and sensitivity analysis in relation to external events

    International Nuclear Information System (INIS)

    Alzbutas, R.; Urbonas, R.; Augutis, J.

    2001-01-01

    This paper presents risk and sensitivity analysis of external events impacts on the safe operation in general and in particular the Ignalina Nuclear Power Plant safety systems. Analysis is based on the deterministic and probabilistic assumptions and assessment of the external hazards. The real statistic data are used as well as initial external event simulation. The preliminary screening criteria are applied. The analysis of external event impact on the NPP safe operation, assessment of the event occurrence, sensitivity analysis, and recommendations for safety improvements are performed for investigated external hazards. Such events as aircraft crash, extreme rains and winds, forest fire and flying parts of the turbine are analysed. The models are developed and probabilities are calculated. As an example for sensitivity analysis the model of aircraft impact is presented. The sensitivity analysis takes into account the uncertainty features raised by external event and its model. Even in case when the external events analysis show rather limited danger, the sensitivity analysis can determine the highest influence causes. These possible variations in future can be significant for safety level and risk based decisions. Calculations show that external events cannot significantly influence the safety level of the Ignalina NPP operation, however the events occurrence and propagation can be sufficiently uncertain.(author)

  18. Application of a new technique for human event analysis (ATHEANA) at a pressurized-water reactor

    International Nuclear Information System (INIS)

    Forester, J.A.; Kiper, K.; Ramey-Smith, A.

    1998-04-01

    Over the past several years, the US Nuclear Regulatory Commission (NRC) has sponsored the development of a new method for performing human reliability analyses (HRAs). A major impetus for the program was the recognized need for a method that would not only address errors of omission (EOOs), but also errors of commission (EOCs). Although several documents have been issued describing the basis and development of the new method referred to as ''A Technique for Human Event Analysis'' (ATHEANA), two documents were drafted to initially provide the necessary documentation for applying the method: the frame of reference (FOR) manual, which served as the technical basis document for the method and the implementation guideline (IG), which provided step by step guidance for applying the method. Upon the completion of the draft FOR manual and the draft IG in April 1997, along with several step-throughs of the process by the development team, the method was ready for a third-party test. The method was demonstrated at Seabrook Station in July 1997. The main goals of the demonstration were to (1) test the ATHENA process as described in the FOR manual and the IG, (2) test a training package developed for the method, (3) test the hypothesis that plant operators and trainers have significant insight into the EFCs that can make UAs more likely, and (4) identify ways to improve the method and its documentation. The results of the Seabrook demonstration are evaluated against the success criteria, and important findings and recommendations regarding ATHENA that were obtained from the demonstration are presented here

  19. Joint Attributes and Event Analysis for Multimedia Event Detection.

    Science.gov (United States)

    Ma, Zhigang; Chang, Xiaojun; Xu, Zhongwen; Sebe, Nicu; Hauptmann, Alexander G

    2017-06-15

    Semantic attributes have been increasingly used the past few years for multimedia event detection (MED) with promising results. The motivation is that multimedia events generally consist of lower level components such as objects, scenes, and actions. By characterizing multimedia event videos with semantic attributes, one could exploit more informative cues for improved detection results. Much existing work obtains semantic attributes from images, which may be suboptimal for video analysis since these image-inferred attributes do not carry dynamic information that is essential for videos. To address this issue, we propose to learn semantic attributes from external videos using their semantic labels. We name them video attributes in this paper. In contrast with multimedia event videos, these external videos depict lower level contents such as objects, scenes, and actions. To harness video attributes, we propose an algorithm established on a correlation vector that correlates them to a target event. Consequently, we could incorporate video attributes latently as extra information into the event detector learnt from multimedia event videos in a joint framework. To validate our method, we perform experiments on the real-world large-scale TRECVID MED 2013 and 2014 data sets and compare our method with several state-of-the-art algorithms. The experiments show that our method is advantageous for MED.

  20. Analysis of human performance problems at the Swedish nuclear power plants

    International Nuclear Information System (INIS)

    Bento, J.P.

    1988-01-01

    The last five years of operation of all Swedish nuclear power plants have been studied with respect to human performance problems by analysing all scrams and licensee event reports (LERs). Thus, the study covers 165 scrams and 1318 LERs. As general results, 39% of the scrams and 27% of the LERs, as an average for the years 1983-1987, are caused by human performance problems. Among the items studied, emphasis has been put on the analysis of the causal categories involved in human performance problems resulting in plant events. The most significant causal categories appear to be Work organization, Procedures not followed, Work place ergonomics and Human variability

  1. External events analysis of the Ignalina Nuclear Power Plant

    International Nuclear Information System (INIS)

    Liaukonis, Mindaugas; Augutis, Juozas

    1999-01-01

    This paper presents analysis of external events impact on the safe operation of the Ignalina Nuclear Power Plant (INPP) safety systems. Analysis was based on the probabilistic estimation and modelling of the external hazards. The screening criteria were applied to the number of external hazards. The following external events such as aircraft failure on the INPP, external flooding, fire, extreme winds requiring further bounding study were analysed. Mathematical models were developed and event probabilities were calculated. External events analysis showed rather limited external events danger to Ignalina NPP. Results of the analysis were compared to analogous analysis in western NPPs and no great differences were specified. Calculations performed show that external events can not significantly influence the safety level of the Ignalina NPP operation. (author)

  2. Incidence of patient safety events and process-related human failures during intra-hospital transportation of patients: retrospective exploration from the institutional incident reporting system.

    Science.gov (United States)

    Yang, Shu-Hui; Jerng, Jih-Shuin; Chen, Li-Chin; Li, Yu-Tsu; Huang, Hsiao-Fang; Wu, Chao-Ling; Chan, Jing-Yuan; Huang, Szu-Fen; Liang, Huey-Wen; Sun, Jui-Sheng

    2017-11-03

    Intra-hospital transportation (IHT) might compromise patient safety because of different care settings and higher demand on the human operation. Reports regarding the incidence of IHT-related patient safety events and human failures remain limited. To perform a retrospective analysis of IHT-related events, human failures and unsafe acts. A hospital-wide process for the IHT and database from the incident reporting system in a medical centre in Taiwan. All eligible IHT-related patient safety events between January 2010 to December 2015 were included. Incidence rate of IHT-related patient safety events, human failure modes, and types of unsafe acts. There were 206 patient safety events in 2 009 013 IHT sessions (102.5 per 1 000 000 sessions). Most events (n=148, 71.8%) did not involve patient harm, and process events (n=146, 70.9%) were most common. Events at the location of arrival (n=101, 49.0%) were most frequent; this location accounted for 61.0% and 44.2% of events with patient harm and those without harm, respectively (pprocess step was the preparation of the transportation team (n=91, 48.9%). Contributing unsafe acts included perceptual errors (n=14, 7.5%), decision errors (n=56, 30.1%), skill-based errors (n=48, 25.8%), and non-compliance (n=68, 36.6%). Multivariate analysis showed that human failure found in the arrival and hand-off sub-process (OR 4.84, pprocess at the location of arrival and prevent errors other than omissions. Long-term monitoring of IHT-related events is also warranted. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  3. Negated bio-events: analysis and identification

    Science.gov (United States)

    2013-01-01

    Background Negation occurs frequently in scientific literature, especially in biomedical literature. It has previously been reported that around 13% of sentences found in biomedical research articles contain negation. Historically, the main motivation for identifying negated events has been to ensure their exclusion from lists of extracted interactions. However, recently, there has been a growing interest in negative results, which has resulted in negation detection being identified as a key challenge in biomedical relation extraction. In this article, we focus on the problem of identifying negated bio-events, given gold standard event annotations. Results We have conducted a detailed analysis of three open access bio-event corpora containing negation information (i.e., GENIA Event, BioInfer and BioNLP’09 ST), and have identified the main types of negated bio-events. We have analysed the key aspects of a machine learning solution to the problem of detecting negated events, including selection of negation cues, feature engineering and the choice of learning algorithm. Combining the best solutions for each aspect of the problem, we propose a novel framework for the identification of negated bio-events. We have evaluated our system on each of the three open access corpora mentioned above. The performance of the system significantly surpasses the best results previously reported on the BioNLP’09 ST corpus, and achieves even better results on the GENIA Event and BioInfer corpora, both of which contain more varied and complex events. Conclusions Recently, in the field of biomedical text mining, the development and enhancement of event-based systems has received significant interest. The ability to identify negated events is a key performance element for these systems. We have conducted the first detailed study on the analysis and identification of negated bio-events. Our proposed framework can be integrated with state-of-the-art event extraction systems. The

  4. External events analysis for experimental fusion facilities

    International Nuclear Information System (INIS)

    Cadwallader, L.C.

    1990-01-01

    External events are those off-normal events that threaten facilities either from outside or inside the building. These events, such as floods, fires, and earthquakes, are among the leading risk contributors for fission power plants, and the nature of fusion facilities indicates that they may also lead fusion risk. This paper gives overviews of analysis methods, references good analysis guidance documents, and gives design tips for mitigating the effects of floods and fires, seismic events, and aircraft impacts. Implications for future fusion facility siting are also discussed. Sites similar to fission plant sites are recommended. 46 refs

  5. Internal event analysis for Laguna Verde Unit 1 Nuclear Power Plant. Accident sequence quantification and results

    International Nuclear Information System (INIS)

    Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R.

    1994-01-01

    The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the I nternal Event Analysis for Laguna Verde Unit 1 Nuclear Power Plant, CNSNS-TR 004, in five volumes. The reports are organized as follows: CNSNS-TR 004 Volume 1: Introduction and Methodology. CNSNS-TR4 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR 004 Volume 3: System Analysis. CNSNS-TR 004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR 005 Volume 5: Appendices A, B and C. This volume presents the development of the dependent failure analysis, the treatment of the support system dependencies, the identification of the shared-components dependencies, and the treatment of the common cause failure. It is also presented the identification of the main human actions considered along with the possible recovery actions included. The development of the data base and the assumptions and limitations in the data base are also described in this volume. The accident sequences quantification process and the resolution of the core vulnerable sequences are presented. In this volume, the source and treatment of uncertainties associated with failure rates, component unavailabilities, initiating event frequencies, and human error probabilities are also presented. Finally, the main results and conclusions for the Internal Event Analysis for Laguna Verde Nuclear Power Plant are presented. The total core damage frequency calculated is 9.03x 10-5 per year for internal events. The most dominant accident sequences found are the transients involving the loss of offsite power, the station blackout accidents, and the anticipated transients without SCRAM (ATWS). (Author)

  6. Human health implications of extreme precipitation events and water quality in California, USA: a canonical correlation analysis

    Directory of Open Access Journals (Sweden)

    Alexander Gershunov, PhD

    2018-05-01

    Full Text Available Background: Pathogens and pollutants collect on the land surface or in infrastructure between strong rainfall episodes and are delivered via storm runoff to areas of human exposure, such as coastal recreational waters. In California, USA, precipitation events are projected to become more extreme and simultaneously decrease in frequency as storm tracks move poleward due to polar-amplified global warming. Precipitation extremes in California are dominated by atmospheric rivers, which carry more moisture in warmer climates. Thus, the physical driver of extreme precipitation events is expected to grow stronger with climate change, and pollutant accumulation and runoff-generated exposure to those pollutants are expected to increase, particularly after prolonged dry spells. Microbiological contamination of coastal waters during winter storms exposes human populations to elevated concentrations of microorganisms such as faecal bacteria, which could cause gastrointestinal and ear infections, and lead to exposure to pathogens causing life-threatening conditions, such as hepatitis A. The aim of this study was to quantitatively assess the effect of precipitation on coastal water quality in California. Methods: We used a recently published catalogue of atmospheric rivers, in combination with historical daily precipitation data and levels of three indicators of faecal bacteria (total and faecal coliforms, and Escherichia coli detected at roughly 500 monitoring locations in coastal waters along California's 840-mile coastline, to explore weekly associations between extreme precipitation events, particularly those related to atmospheric rivers, and the variability in water quality during 2003–09. We identified ten principal components (together explaining >90% of the variability in precipitation and faecal bacteria time-series to reduce the dimensionality of the datasets. We then performed canonical correlation analysis of the principal components to

  7. Analysis of extreme events

    CSIR Research Space (South Africa)

    Khuluse, S

    2009-04-01

    Full Text Available ) determination of the distribution of the damage and (iii) preparation of products that enable prediction of future risk events. The methodology provided by extreme value theory can also be a powerful tool in risk analysis...

  8. LOSP-initiated event tree analysis for BWR

    International Nuclear Information System (INIS)

    Watanabe, Norio; Kondo, Masaaki; Uno, Kiyotaka; Chigusa, Takeshi; Harami, Taikan

    1989-03-01

    As a preliminary study of 'Japanese Model Plant PSA', a LOSP (loss of off-site power)-initiated Event Tree Analysis for a Japanese typical BWR was carried out solely based on the open documents such as 'Safety Analysis Report'. The objectives of this analysis are as follows; - to delineate core-melt accident sequences initiated by LOSP, - to evaluate the importance of core-melt accident sequences in terms of occurrence frequency, and - to develop a foundation of plant information and analytical procedures for efficiently performing further 'Japanese Model Plant PSA'. This report describes the procedure and results of the LOSP-initiated Event Tree Analysis. In this analysis, two types of event trees, Functional Event Tree and Systemic Event Tree, were developed to delineate core-melt accident sequences and to quantify their frequencies. Front-line System Event Tree was prepared as well to provide core-melt sequence delineation for accident progression analysis of Level 2 PSA which will be followed in a future. Applying U.S. operational experience data such as component failure rates and a LOSP frequency, we obtained the following results; - The total frequency of core-melt accident sequences initiated by LOSP is estimated at 5 x 10 -4 per reactor-year. - The dominant sequences are 'Loss of Decay Heat Removal' and 'Loss of Emergency Electric Power Supply', which account for more than 90% of the total core-melt frequency. In this analysis, a higher value of 0.13/R·Y was used for the LOSP frequency than experiences in Japan and any recovery action was not considered. In fact, however, there has been no experience of LOSP event in Japanese nuclear power plants so far and it is also expected that offsite power and/or PCS would be recovered before core melt. Considering Japanese operating experience and recovery factors will reduce the total core-melt frequency to less than 10 -6 per reactor-year. (J.P.N.)

  9. Human reliability analysis for steam generator feed-and-bleed accident in Bushehr NPP-1

    Energy Technology Data Exchange (ETDEWEB)

    Jafarian, Reza [Valiasr University of Rafsanjan, Rafsanjan, 28 (Iran, Islamic Republic of); Sepanloo, Kamran [Atomic Energy Organization of Iran (AEOI), external link End of North Karegar Av., Tehran 14155-1339 (Iran, Islamic Republic of)

    2006-07-01

    According to the incident/accident reports, unsuccessful implementation of steam generator feed-and-bleed procedure is one of the most important events in nuclear power plants operation which greatly contributes to the level of risk of the plants. Generally, the loss of all feed water pumps flow (as one of the precursors) results in failure to maintain adequate cooling of the reactor core unless the operating crew initiate and follow the feed-and-bleed procedure correctly and timely. In this paper, firstly, a Human Reliability Analysis (HRA) event tree is presented delineating the major human activities and errors in the implementation of the steam generator (SG) feed-and-bleed procedure following the loss of (both normal and emergency) water feed to four SGs of Bushehr Nuclear Power Plant Unit 1 (BNPP-1). Secondly, the graphical method of task analysis as a part of HRA is used as a means of delineating correct and incorrect human actions. To be used in the probabilistic risk assessment (PRA), the outputs of the HRA event trees are fed into the system event trees, functional event trees or system fault trees. As a part of a probabilistic risk assessment of BNPP-1 and to assess the reliability of control room operators, a human reliability analysis model is applied based on the THERP (Technique for Human Error Rate Prediction) technique. The THERP method is used in the form of event trees named as the probability tree diagrams. In this research the Human Reliability Analysis event tree is constructed based on the background information and assumptions made and on a similar NPP task analysis. It is done so because the BNPP-1 is not an operational nuclear power plant. Thirdly, based on NUREG/CR-1278 Handbook, a computer program has been developed in Visual Basic language and used to illustrate the major human activities and determination of error rates of operators in the course of the implementation of the steam generator feed-and-bleed procedure. Finally, total

  10. Human reliability analysis in Loviisa probabilistic safety analysis

    International Nuclear Information System (INIS)

    Illman, L.; Isaksson, J.; Makkonen, L.; Vaurio, J.K.; Vuorio, U.

    1986-01-01

    The human reliability analysis in the Loviisa PSA project is carried out for three major groups of errors in human actions: (A) errors made before an initiating event, (B) errors that initiate a transient and (C) errors made during transients. Recovery possibilities are also included in each group. The methods used or planned for each group are described. A simplified THERP approach is used for group A, with emphasis on test and maintenance error recovery aspects and dependencies between redundancies. For group B, task analyses and human factors assessments are made for startup, shutdown and operational transients, with emphasis on potential common cause initiators. For group C, both misdiagnosis and slow decision making are analyzed, as well as errors made in carrying out necessary or backup actions. New or advanced features of the methodology are described

  11. Event driven adaptation, land use and human coping strategies

    DEFF Research Database (Denmark)

    Reenberg, Anette; Birch-Thomsen, Torben; Fog, Bjarne

    perceive cause-effect relationships between societal and environmental events and their individual and collective management of resources. The coupled human-environment timelines are used to discuss ways in which the local communities' adaptive resource management strategies have been employed in the face......The paper focuses on assessing the wider perspectives of adaptive resource management strategies in former subsistence agriculture societies in the SW Pacific. Firstly, we will briefly introduce the theoretical context related to the livelihood framework, adaptation to socio-environmental change...... and the concept of coupled human-environmental timelines. Secondly, with point of departure in a baseline characterization of Bellona Island derived from a comprehensive survey in the late 1960s and resent fieldwork in late 2006, we present the case of Bellona Island. Key issues addressed concern climatic events...

  12. Systamatic approach to integration of a human reliability analysis into a NPP probabalistic risk assessment

    International Nuclear Information System (INIS)

    Fragola, J.R.

    1984-01-01

    This chapter describes the human reliability analysis tasks which were employed in the evaluation of the overall probability of an internal flood sequence and its consequences in terms of disabling vulnerable risk significant equipment. Topics considered include the problem familiarization process, the identification and classification of key human interactions, a human interaction review of potential initiators, a maintenance and operations review, human interaction identification, quantification model selection, the definition of operator-induced sequences, the quantification of specific human interactions, skill- and rule-based interactions, knowledge-based interactions, and the incorporation of human interaction-related events into the event tree structure. It is concluded that an integrated approach to the analysis of human interaction within the context of a Probabilistic Risk Assessment (PRA) is feasible

  13. Trend and pattern analysis of human performance problems at the swedish nuclear power plants

    International Nuclear Information System (INIS)

    Bento, J.P.

    1990-01-01

    The last six years of operation of all Swedish nuclear power plants have been studied with respect to human performance problems by analysing all scrams and licensee event reports (LERs). The present paper is an updated version of a previous report to which the analysis results of the year 1988's events have been added. The study covers 197 scrams and 1759 LERs. As general results, 38% of the scrams and 27% of the LERs, as an average for the years 1983-1988, are caused by human performance problems. Among the items studied, emphasis has been put on the analysis of the causal categories involved in human performance problems resulting in plant events. The most significant causal categories appear to be Work organization, Work place ergonomics, Procedures not followed, Training and Human variability. The trend and pattern of the dominating causal categories are discussed

  14. TEMAC, Top Event Sensitivity Analysis

    International Nuclear Information System (INIS)

    Iman, R.L.; Shortencarier, M.J.

    1988-01-01

    1 - Description of program or function: TEMAC is designed to permit the user to easily estimate risk and to perform sensitivity and uncertainty analyses with a Boolean expression such as produced by the SETS computer program. SETS produces a mathematical representation of a fault tree used to model system unavailability. In the terminology of the TEMAC program, such a mathematical representation is referred to as a top event. The analysis of risk involves the estimation of the magnitude of risk, the sensitivity of risk estimates to base event probabilities and initiating event frequencies, and the quantification of the uncertainty in the risk estimates. 2 - Method of solution: Sensitivity and uncertainty analyses associated with top events involve mathematical operations on the corresponding Boolean expression for the top event, as well as repeated evaluations of the top event in a Monte Carlo fashion. TEMAC employs a general matrix approach which provides a convenient general form for Boolean expressions, is computationally efficient, and allows large problems to be analyzed. 3 - Restrictions on the complexity of the problem - Maxima of: 4000 cut sets, 500 events, 500 values in a Monte Carlo sample, 16 characters in an event name. These restrictions are implemented through the FORTRAN 77 PARAMATER statement

  15. A Key Event Path Analysis Approach for Integrated Systems

    Directory of Open Access Journals (Sweden)

    Jingjing Liao

    2012-01-01

    Full Text Available By studying the key event paths of probabilistic event structure graphs (PESGs, a key event path analysis approach for integrated system models is proposed. According to translation rules concluded from integrated system architecture descriptions, the corresponding PESGs are constructed from the colored Petri Net (CPN models. Then the definitions of cycle event paths, sequence event paths, and key event paths are given. Whereafter based on the statistic results after the simulation of CPN models, key event paths are found out by the sensitive analysis approach. This approach focuses on the logic structures of CPN models, which is reliable and could be the basis of structured analysis for discrete event systems. An example of radar model is given to characterize the application of this approach, and the results are worthy of trust.

  16. Modeling human reliability analysis using MIDAS

    International Nuclear Information System (INIS)

    Boring, R. L.

    2006-01-01

    This paper documents current efforts to infuse human reliability analysis (HRA) into human performance simulation. The Idaho National Laboratory is teamed with NASA Ames Research Center to bridge the SPAR-H HRA method with NASA's Man-machine Integration Design and Analysis System (MIDAS) for use in simulating and modeling the human contribution to risk in nuclear power plant control room operations. It is anticipated that the union of MIDAS and SPAR-H will pave the path for cost-effective, timely, and valid simulated control room operators for studying current and next generation control room configurations. This paper highlights considerations for creating the dynamic HRA framework necessary for simulation, including event dependency and granularity. This paper also highlights how the SPAR-H performance shaping factors can be modeled in MIDAS across static, dynamic, and initiator conditions common to control room scenarios. This paper concludes with a discussion of the relationship of the workload factors currently in MIDAS and the performance shaping factors in SPAR-H. (authors)

  17. Statistical analysis of solar proton events

    Directory of Open Access Journals (Sweden)

    V. Kurt

    2004-06-01

    Full Text Available A new catalogue of 253 solar proton events (SPEs with energy >10MeV and peak intensity >10 protons/cm2.s.sr (pfu at the Earth's orbit for three complete 11-year solar cycles (1970-2002 is given. A statistical analysis of this data set of SPEs and their associated flares that occurred during this time period is presented. It is outlined that 231 of these proton events are flare related and only 22 of them are not associated with Ha flares. It is also noteworthy that 42 of these events are registered as Ground Level Enhancements (GLEs in neutron monitors. The longitudinal distribution of the associated flares shows that a great number of these events are connected with west flares. This analysis enables one to understand the long-term dependence of the SPEs and the related flare characteristics on the solar cycle which are useful for space weather prediction.

  18. Analysis of core damage frequency from internal events: Methodology guidelines: Volume 1

    International Nuclear Information System (INIS)

    Drouin, M.T.; Harper, F.T.; Camp, A.L.

    1987-09-01

    NUREG-1150 examines the risk to the public from a selected group of nuclear power plants. This report describes the methodology used to estimate the internal event core damage frequencies of four plants in support of NUREG-1150. In principle, this methodology is similar to methods used in past probabilistic risk assessments; however, based on past studies and using analysts that are experienced in these techniques, the analyses can be focused in certain areas. In this approach, only the most important systems and failure modes are modeled in detail. Further, the data and human reliability analyses are simplified, with emphasis on the most important components and human actions. Using these methods, an analysis can be completed in six to nine months using two to three full-time systems analysts and part-time personnel in other areas, such as data analysis and human reliability analysis. This is significantly faster and less costly than previous analyses and provides most of the insights that are obtained by the more costly studies. 82 refs., 35 figs., 27 tabs

  19. Event History Analysis in Quantitative Genetics

    DEFF Research Database (Denmark)

    Maia, Rafael Pimentel

    Event history analysis is a clas of statistical methods specially designed to analyze time-to-event characteristics, e.g. the time until death. The aim of the thesis was to present adequate multivariate versions of mixed survival models that properly represent the genetic aspects related to a given...

  20. Sentiment analysis on tweets for social events

    DEFF Research Database (Denmark)

    Zhou, Xujuan; Tao, Xiaohui; Yong, Jianming

    2013-01-01

    Sentiment analysis or opinion mining is an important type of text analysis that aims to support decision making by extracting and analyzing opinion oriented text, identifying positive and negative opinions, and measuring how positively or negatively an entity (i.e., people, organization, event......, location, product, topic, etc.) is regarded. As more and more users express their political and religious views on Twitter, tweets become valuable sources of people's opinions. Tweets data can be efficiently used to infer people's opinions for marketing or social studies. This paper proposes a Tweets...... Sentiment Analysis Model (TSAM) that can spot the societal interest and general people's opinions in regard to a social event. In this paper, Australian federal election 2010 event was taken as an example for sentiment analysis experiments. We are primarily interested in the sentiment of the specific...

  1. Application of DFM in human reliability analysis

    International Nuclear Information System (INIS)

    Yu Shaojie; Zhao Jun; Tong Jiejuan

    2011-01-01

    Combining with ATHEANA, the possible to identify EFCs and UAs using DFM is studied; and then Steam Generator Tube Rupture (SGTR) accident is modeled and solved. Through inductive analysis, 26 Prime Implicants (PIs) are obtained and the meaning of results is interpreted; and one of PIs is similar to the accident scenario of human failure event in one nuclear power plant. Finally, this paper discusses the methods of quantifying PIs, analysis of Error of commission (EOC) and so on. (authors)

  2. Interpretation Analysis as a Competitive Event.

    Science.gov (United States)

    Nading, Robert M.

    Interpretation analysis is a new and interesting event on the forensics horizon which appears to be attracting an ever larger number of supporters. This event, developed by Larry Lambert of Ball State University in 1989, requires a student to perform all three disciplines of forensic competition (interpretation, public speaking, and limited…

  3. Nonlinear impacts of small-scale natural events on Nineteenth Century human decision-making

    Science.gov (United States)

    McCormack, S. M.; Schlichting, K. M.; Urbanova, T.; Allen, T. L.; Ruffing, C. M.; Hermans, C. M.

    2009-12-01

    Natural climatological events that occurred throughout the Nineteenth Century, such as floods, droughts and hurricanes had long-lived, far-reaching consequences on the human decision-making processes occurring in the northeast United States. These events impacted the hydrological cycle, both directly -though the building of various structures- and indirectly - through an increased understanding of science; and the changing relationship between humans and their environment. This paper examines these events and associated processes through: 1) identifying specific natural events throughout the time period, occurring globally, with initial conditions conducive to long-lived consequences; 2) examining the relationship between scientific enquiry, natural events and the proliferation of dams in the northeast landscape; and 3) the growth of public health concerns, awareness of bacteriology, and municipal water supply systems. Results of this research indicate that the relationship between knowledge systems, natural events and subsequent engineering or technological fixes is complex and highly dependent on initial conditions. It highlights the time period where humans became increasingly dependent on engineered solutions to environmental problems, many of which still hold fast in our contemporary landscape. It is relevant to natural, social and governance structures in place today. The principles behind the occurrence of the natural phenomena and subsequent research and design have not changed; and understanding key events or stages in the past is tantamount to making predictions for the future.

  4. Advanced event reweighting using multivariate analysis

    International Nuclear Information System (INIS)

    Martschei, D; Feindt, M; Honc, S; Wagner-Kuhr, J

    2012-01-01

    Multivariate analysis (MVA) methods, especially discrimination techniques such as neural networks, are key ingredients in modern data analysis and play an important role in high energy physics. They are usually trained on simulated Monte Carlo (MC) samples to discriminate so called 'signal' from 'background' events and are then applied to data to select real events of signal type. We here address procedures that improve this work flow. This will be the enhancement of data / MC agreement by reweighting MC samples on a per event basis. Then training MVAs on real data using the sPlot technique will be discussed. Finally we will address the construction of MVAs whose discriminator is independent of a certain control variable, i.e. cuts on this variable will not change the discriminator shape.

  5. Poisson-event-based analysis of cell proliferation.

    Science.gov (United States)

    Summers, Huw D; Wills, John W; Brown, M Rowan; Rees, Paul

    2015-05-01

    A protocol for the assessment of cell proliferation dynamics is presented. This is based on the measurement of cell division events and their subsequent analysis using Poisson probability statistics. Detailed analysis of proliferation dynamics in heterogeneous populations requires single cell resolution within a time series analysis and so is technically demanding to implement. Here, we show that by focusing on the events during which cells undergo division rather than directly on the cells themselves a simplified image acquisition and analysis protocol can be followed, which maintains single cell resolution and reports on the key metrics of cell proliferation. The technique is demonstrated using a microscope with 1.3 μm spatial resolution to track mitotic events within A549 and BEAS-2B cell lines, over a period of up to 48 h. Automated image processing of the bright field images using standard algorithms within the ImageJ software toolkit yielded 87% accurate recording of the manually identified, temporal, and spatial positions of the mitotic event series. Analysis of the statistics of the interevent times (i.e., times between observed mitoses in a field of view) showed that cell division conformed to a nonhomogeneous Poisson process in which the rate of occurrence of mitotic events, λ exponentially increased over time and provided values of the mean inter mitotic time of 21.1 ± 1.2 hours for the A549 cells and 25.0 ± 1.1 h for the BEAS-2B cells. Comparison of the mitotic event series for the BEAS-2B cell line to that predicted by random Poisson statistics indicated that temporal synchronisation of the cell division process was occurring within 70% of the population and that this could be increased to 85% through serum starvation of the cell culture. © 2015 International Society for Advancement of Cytometry.

  6. An assessment of the risk significance of human errors in selected PSAs and operating events

    International Nuclear Information System (INIS)

    Palla, R.L. Jr.; El-Bassioni, A.

    1991-01-01

    Sensitivity studies based on Probabilistic Safety Assessments (PSAs) for a pressurized water reactor and a boiling water reactor are described. In each case human errors modeled in the PSAs were categorized according to such factors as error type, location, timing, and plant personnel involved. Sensitivity studies were then conducted by varying the error rates in each category and evaluating the corresponding change in total core damage frequency and accident sequence frequency. Insights obtained are discussed and reasons for differences in risk sensitivity between plants are explored. A separate investigation into the role of human error in risk-important operating events is also described. This investigation involved the analysis of data from the USNRC Accident Sequence Precursor program to determine the effect of operator-initiated events on accident precursor trends, and to determine whether improved training can be correlated to current trends. The findings of this study are also presented. 5 refs., 15 figs., 1 tab

  7. Corrective action program at the Krsko NPP. Trending and analysis of minor events

    International Nuclear Information System (INIS)

    Bach, B.; Kavsek, D.

    2007-01-01

    Industry and On-site Operating Experience has shown that the significant events, minor events and near misses all share something in common: latent weaknesses that result in failed barriers and the same or similar (root) causes for that failure. All these types of events differ only in their resulting consequences: minor events and near misses have no immediate or significant impact to plant safety or reliability. However, the significant events are usually preceded by a number of those kinds of events and could be prevented from occurring if the root cause(s) of these precursor events could be identified and eliminated. It would be therefore poor management to leave minor events and near misses unreported and unanalysed. Reporting and analysing of minor events allows detection of latent weaknesses that may indicate the need for improvement. The benefit of low level event analysis is that deficiencies can be found in barriers that normally go unchallenged and may not be known that they are ineffective in stopping a significant event. In addition, large numbers of minor events and near misses may increase the probability of occurrence of a significant event, which in itself is a sufficient reason for addressing these types of events. However, as it is not often practical neither feasible to perform a detailed root cause determination for every minor events, trending and trend analysis are used to identify and correct the causes prior to their resulting in a significant event. Trending is monitoring a change in frequency of similar minor events occurrence. Adverse trend is an increase in the frequency of minor events which are sorted by commonality such as common equipment failure, human factors, common or similar causal factors, activity etc. or worsening performance of processes that has been trending. The primary goal of any trending programme should be to identify an adverse trend early enough that the operating organization can initiate an investigation to help

  8. Human error and the problem of causality in analysis of accidents

    DEFF Research Database (Denmark)

    Rasmussen, Jens

    1990-01-01

    , designers or managers have played a major role. There are, however, several basic problems in analysis of accidents and identification of human error. This paper addresses the nature of causal explanations and the ambiguity of the rules applied for identification of the events to include in analysis......Present technology is characterized by complexity, rapid change and growing size of technical systems. This has caused increasing concern with the human involvement in system safety. Analyses of the major accidents during recent decades have concluded that human errors on part of operators...

  9. Surface Management System Departure Event Data Analysis

    Science.gov (United States)

    Monroe, Gilena A.

    2010-01-01

    This paper presents a data analysis of the Surface Management System (SMS) performance of departure events, including push-back and runway departure events.The paper focuses on the detection performance, or the ability to detect departure events, as well as the prediction performance of SMS. The results detail a modest overall detection performance of push-back events and a significantly high overall detection performance of runway departure events. The overall detection performance of SMS for push-back events is approximately 55%.The overall detection performance of SMS for runway departure events nears 100%. This paper also presents the overall SMS prediction performance for runway departure events as well as the timeliness of the Aircraft Situation Display for Industry data source for SMS predictions.

  10. Second-order analysis of semiparametric recurrent event processes.

    Science.gov (United States)

    Guan, Yongtao

    2011-09-01

    A typical recurrent event dataset consists of an often large number of recurrent event processes, each of which contains multiple event times observed from an individual during a follow-up period. Such data have become increasingly available in medical and epidemiological studies. In this article, we introduce novel procedures to conduct second-order analysis for a flexible class of semiparametric recurrent event processes. Such an analysis can provide useful information regarding the dependence structure within each recurrent event process. Specifically, we will use the proposed procedures to test whether the individual recurrent event processes are all Poisson processes and to suggest sensible alternative models for them if they are not. We apply these procedures to a well-known recurrent event dataset on chronic granulomatous disease and an epidemiological dataset on meningococcal disease cases in Merseyside, United Kingdom to illustrate their practical value. © 2011, The International Biometric Society.

  11. Estimating the impact of extreme events on crude oil price. An EMD-based event analysis method

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xun; Wang, Shouyang [Institute of Systems Science, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China); School of Mathematical Sciences, Graduate University of Chinese Academy of Sciences, Beijing 100190 (China); Yu, Lean [Institute of Systems Science, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, Beijing 100190 (China); Lai, Kin Keung [Department of Management Sciences, City University of Hong Kong, Tat Chee Avenue, Kowloon (China)

    2009-09-15

    The impact of extreme events on crude oil markets is of great importance in crude oil price analysis due to the fact that those events generally exert strong impact on crude oil markets. For better estimation of the impact of events on crude oil price volatility, this study attempts to use an EMD-based event analysis approach for this task. In the proposed method, the time series to be analyzed is first decomposed into several intrinsic modes with different time scales from fine-to-coarse and an average trend. The decomposed modes respectively capture the fluctuations caused by the extreme event or other factors during the analyzed period. It is found that the total impact of an extreme event is included in only one or several dominant modes, but the secondary modes provide valuable information on subsequent factors. For overlapping events with influences lasting for different periods, their impacts are separated and located in different modes. For illustration and verification purposes, two extreme events, the Persian Gulf War in 1991 and the Iraq War in 2003, are analyzed step by step. The empirical results reveal that the EMD-based event analysis method provides a feasible solution to estimating the impact of extreme events on crude oil prices variation. (author)

  12. Estimating the impact of extreme events on crude oil price. An EMD-based event analysis method

    International Nuclear Information System (INIS)

    Zhang, Xun; Wang, Shouyang; Yu, Lean; Lai, Kin Keung

    2009-01-01

    The impact of extreme events on crude oil markets is of great importance in crude oil price analysis due to the fact that those events generally exert strong impact on crude oil markets. For better estimation of the impact of events on crude oil price volatility, this study attempts to use an EMD-based event analysis approach for this task. In the proposed method, the time series to be analyzed is first decomposed into several intrinsic modes with different time scales from fine-to-coarse and an average trend. The decomposed modes respectively capture the fluctuations caused by the extreme event or other factors during the analyzed period. It is found that the total impact of an extreme event is included in only one or several dominant modes, but the secondary modes provide valuable information on subsequent factors. For overlapping events with influences lasting for different periods, their impacts are separated and located in different modes. For illustration and verification purposes, two extreme events, the Persian Gulf War in 1991 and the Iraq War in 2003, are analyzed step by step. The empirical results reveal that the EMD-based event analysis method provides a feasible solution to estimating the impact of extreme events on crude oil prices variation. (author)

  13. Paleo-event data standards for dendrochronology

    Science.gov (United States)

    Elaine Kennedy Sutherland; P. Brewer; W. Gross

    2017-01-01

    Extreme environmental events, such as storm winds, landslides, insect infestations, and wildfire, cause loss of life, resources, and human infrastructure. Disaster riskreduction analysis can be improved with information about past frequency, intensity, and spatial patterns of extreme events. Tree-ring analyses can provide such information: tree rings reflect events as...

  14. The Recording and Quantification of Event-Related Potentials: II. Signal Processing and Analysis

    Directory of Open Access Journals (Sweden)

    Paniz Tavakoli

    2015-06-01

    Full Text Available Event-related potentials are an informative method for measuring the extent of information processing in the brain. The voltage deflections in an ERP waveform reflect the processing of sensory information as well as higher-level processing that involves selective attention, memory, semantic comprehension, and other types of cognitive activity. ERPs provide a non-invasive method of studying, with exceptional temporal resolution, cognitive processes in the human brain. ERPs are extracted from scalp-recorded electroencephalography by a series of signal processing steps. The present tutorial will highlight several of the analysis techniques required to obtain event-related potentials. Some methodological issues that may be encountered will also be discussed.

  15. Social Role Discovery in Human Events (Open Access)

    Science.gov (United States)

    2013-10-03

    to all people in the videos. We also present a novel YouTube social roles dataset with ground truth role annota- tions, and introduce annotations on a... nursing home [13], making role identifi- cation a difficult human task. Ideally, we would like to auto- matically discover such interaction-based role...34# $% &’$( ! Figure 2. Sample frames from different events in the YouTube Social

  16. The dependence level analysis between the human actions in NPP Operation

    International Nuclear Information System (INIS)

    Farcasiu, M.; Nitoi, M.; Apostol, M.; Florescu, G.; Prisecaru, Ilie

    2009-01-01

    The Human Reliability Analysis (HRA) is an important method in Probabilistic Safety Assessment (PSA) studies and offers desirability for concrete improvement of the man - machine - organization interfaces, reliability and safety. An important step in HRA is the dependence level analysis between the human actions performed by the same person or between the actions performed by different persons, step in quantitative analysis of the human errors probabilities. The purpose of this paper is to develop a model to analyze the dependence level between human actions for Nuclear Power Plant (NPP) operation. The model estimates the conditional human error probabilities (CHEP) and joint human error probabilities (JHEP). The achieved sensitivity analyses determine human performance sensibility to systematic variations for dependence level between human actions. The human error probabilities estimated in this paper are adequate values for integration both in HRA and in PSA realized for NPP. This type of analysis helps in finding and analyzing the ways of reducing the likelihood of human errors, so that the impact of human factor to systems availability, reliability and safety can be realistically estimated. In order to demonstrate the usability of this model an analysis is performed upon the dependences between the necessary human actions in mitigating the consequences of LOCA events, particularly for the case of Cernavoda NPP. (authors)

  17. Development of a new cause classification method considering plant ageing and human errors for adverse events which occurred in nuclear power plants and some results of its application

    International Nuclear Information System (INIS)

    Miyazaki, Takamasa

    2007-01-01

    The adverse events which occurred in nuclear power plants are analyzed to prevent similar events, and in the analysis of each event, the cause of the event is classified by a cause classification method. This paper shows a new cause classification method which is improved in several points as follows: (1) the whole causes are systematically classified into three major categories such as machine system, operation system and plant outside causes, (2) the causes of the operation system are classified into several management errors normally performed in a nuclear power plant, (3) the content of ageing is defined in detail for their further analysis, (4) human errors are divided and defined by the error stage, (5) human errors can be related to background factors, and so on. This new method is applied to the adverse events which occurred in domestic and overseas nuclear power plants in 2005. From these results, it is clarified that operation system errors account for about 60% of the whole causes, of which approximately 60% are maintenance errors, about 40% are worker's human errors, and that the prevention of maintenance errors, especially worker's human errors is crucial. (author)

  18. Dynamic Event Tree Analysis Through RAVEN

    Energy Technology Data Exchange (ETDEWEB)

    A. Alfonsi; C. Rabiti; D. Mandelli; J. Cogliati; R. A. Kinoshita; A. Naviglio

    2013-09-01

    Conventional Event-Tree (ET) based methodologies are extensively used as tools to perform reliability and safety assessment of complex and critical engineering systems. One of the disadvantages of these methods is that timing/sequencing of events and system dynamics is not explicitly accounted for in the analysis. In order to overcome these limitations several techniques, also know as Dynamic Probabilistic Risk Assessment (D-PRA), have been developed. Monte-Carlo (MC) and Dynamic Event Tree (DET) are two of the most widely used D-PRA methodologies to perform safety assessment of Nuclear Power Plants (NPP). In the past two years, the Idaho National Laboratory (INL) has developed its own tool to perform Dynamic PRA: RAVEN (Reactor Analysis and Virtual control ENvironment). RAVEN has been designed in a high modular and pluggable way in order to enable easy integration of different programming languages (i.e., C++, Python) and coupling with other application including the ones based on the MOOSE framework, developed by INL as well. RAVEN performs two main tasks: 1) control logic driver for the new Thermo-Hydraulic code RELAP-7 and 2) post-processing tool. In the first task, RAVEN acts as a deterministic controller in which the set of control logic laws (user defined) monitors the RELAP-7 simulation and controls the activation of specific systems. Moreover, RAVEN also models stochastic events, such as components failures, and performs uncertainty quantification. Such stochastic modeling is employed by using both MC and DET algorithms. In the second task, RAVEN processes the large amount of data generated by RELAP-7 using data-mining based algorithms. This paper focuses on the first task and shows how it is possible to perform the analysis of dynamic stochastic systems using the newly developed RAVEN DET capability. As an example, the Dynamic PRA analysis, using Dynamic Event Tree, of a simplified pressurized water reactor for a Station Black-Out scenario is presented.

  19. Human BLCAP transcript: new editing events in normal and cancerous tissues.

    Science.gov (United States)

    Galeano, Federica; Leroy, Anne; Rossetti, Claudia; Gromova, Irina; Gautier, Philippe; Keegan, Liam P; Massimi, Luca; Di Rocco, Concezio; O'Connell, Mary A; Gallo, Angela

    2010-07-01

    Bladder cancer-associated protein (BLCAP) is a highly conserved protein among species, and it is considered a novel candidate tumor suppressor gene originally identified from human bladder carcinoma. However, little is known about the regulation or the function of this protein. Here, we show that the human BLCAP transcript undergoes multiple A-to-I editing events. Some of the new editing events alter the highly conserved amino terminus of the protein creating alternative protein isoforms by changing the genetically coded amino acids. We found that both ADAR1 and ADAR2-editing enzymes cooperate to edit this transcript and that different tissues displayed distinctive ratios of edited and unedited BLCAP transcripts. Moreover, we observed a general decrease in BLCAP-editing level in astrocytomas, bladder cancer and colorectal cancer when compared with the related normal tissues. The newly identified editing events, found to be downregulated in cancers, could be useful for future studies as a diagnostic tool to distinguish malignancies or epigenetic changes in different tumors.

  20. Top event prevention analysis: A deterministic use of PRA

    International Nuclear Information System (INIS)

    Worrell, R.B.; Blanchard, D.P.

    1996-01-01

    This paper describes the application of Top Event Prevention Analysis. The analysis finds prevention sets which are combinations of basic events that can prevent the occurrence of a fault tree top event such as core damage. The problem analyzed in this application is that of choosing a subset of Motor-Operated Valves (MOVs) for testing under the Generic Letter 89-10 program such that the desired level of safety is achieved while providing economic relief from the burden of testing all safety-related valves. A brief summary of the method is given, and the process used to produce a core damage expression from Level 1 PRA models for a PWR is described. The analysis provides an alternative to the use of importance measures for finding the important combination of events in a core damage expression. This application of Top Event Prevention Analysis to the MOV problem was achieve with currently available software

  1. SIMULATED HUMAN ERROR PROBABILITY AND ITS APPLICATION TO DYNAMIC HUMAN FAILURE EVENTS

    Energy Technology Data Exchange (ETDEWEB)

    Herberger, Sarah M.; Boring, Ronald L.

    2016-10-01

    Abstract Objectives: Human reliability analysis (HRA) methods typically analyze human failure events (HFEs) at the overall task level. For dynamic HRA, it is important to model human activities at the subtask level. There exists a disconnect between dynamic subtask level and static task level that presents issues when modeling dynamic scenarios. For example, the SPAR-H method is typically used to calculate the human error probability (HEP) at the task level. As demonstrated in this paper, quantification in SPAR-H does not translate to the subtask level. Methods: Two different discrete distributions were generated for each SPAR-H Performance Shaping Factor (PSF) to define the frequency of PSF levels. The first distribution was a uniform, or uninformed distribution that assumed the frequency of each PSF level was equally likely. The second non-continuous distribution took the frequency of PSF level as identified from an assessment of the HERA database. These two different approaches were created to identify the resulting distribution of the HEP. The resulting HEP that appears closer to the known distribution, a log-normal centered on 1E-3, is the more desirable. Each approach then has median, average and maximum HFE calculations applied. To calculate these three values, three events, A, B and C are generated from the PSF level frequencies comprised of subtasks. The median HFE selects the median PSF level from each PSF and calculates HEP. The average HFE takes the mean PSF level, and the maximum takes the maximum PSF level. The same data set of subtask HEPs yields starkly different HEPs when aggregated to the HFE level in SPAR-H. Results: Assuming that each PSF level in each HFE is equally likely creates an unrealistic distribution of the HEP that is centered at 1. Next the observed frequency of PSF levels was applied with the resulting HEP behaving log-normally with a majority of the values under 2.5% HEP. The median, average and maximum HFE calculations did yield

  2. The Ontology of Vaccine Adverse Events (OVAE) and its usage in representing and analyzing adverse events associated with US-licensed human vaccines.

    Science.gov (United States)

    Marcos, Erica; Zhao, Bin; He, Yongqun

    2013-11-26

    Licensed human vaccines can induce various adverse events (AE) in vaccinated patients. Due to the involvement of the whole immune system and complex immunological reactions after vaccination, it is difficult to identify the relations among vaccines, adverse events, and human populations in different age groups. Many known vaccine adverse events (VAEs) have been recorded in the package inserts of US-licensed commercial vaccine products. To better represent and analyze VAEs, we developed the Ontology of Vaccine Adverse Events (OVAE) as an extension of the Ontology of Adverse Events (OAE) and the Vaccine Ontology (VO). Like OAE and VO, OVAE is aligned with the Basic Formal Ontology (BFO). The commercial vaccines and adverse events in OVAE are imported from VO and OAE, respectively. A new population term 'human vaccinee population' is generated and used to define VAE occurrence. An OVAE design pattern is developed to link vaccine, adverse event, vaccinee population, age range, and VAE occurrence. OVAE has been used to represent and classify the adverse events recorded in package insert documents of commercial vaccines licensed by the USA Food and Drug Administration (FDA). OVAE currently includes over 1,300 terms, including 87 distinct types of VAEs associated with 63 human vaccines licensed in the USA. For each vaccine, occurrence rates for every VAE in different age groups have been logically represented in OVAE. SPARQL scripts were developed to query and analyze the OVAE knowledge base data. To demonstrate the usage of OVAE, the top 10 vaccines accompanying with the highest numbers of VAEs and the top 10 VAEs most frequently observed among vaccines were identified and analyzed. Asserted and inferred ontology hierarchies classify VAEs in different levels of AE groups. Different VAE occurrences in different age groups were also analyzed. The ontology-based data representation and integration using the FDA-approved information from the vaccine package insert documents

  3. Human errors identification using the human factors analysis and classification system technique (HFACS

    Directory of Open Access Journals (Sweden)

    G. A. Shirali

    2013-12-01

    .Result: In this study, 158 reports of accident in Ahvaz steel industry were analyzed by HFACS technique. This analysis showed that most of the human errors were: in the first level was related to the skill-based errors, in the second to the physical environment, in the third level to the inadequate supervision and in the fourth level to the management of resources. .Conclusion: Studying and analyzing of past events using the HFACS technique can identify the major and root causes of accidents and can be effective on prevent repetitions of such mishaps. Also, it can be used as a basis for developing strategies to prevent future events in steel industries.

  4. The analysis of the initiating events in thorium-based molten salt reactor

    International Nuclear Information System (INIS)

    Zuo Jiaxu; Song Wei; Jing Jianping; Zhang Chunming

    2014-01-01

    The initiation events analysis and evaluation were the beginning of nuclear safety analysis and probabilistic safety analysis, and it was the key points of the nuclear safety analysis. Currently, the initiation events analysis method and experiences both focused on water reactor, but no methods and theories for thorium-based molten salt reactor (TMSR). With TMSR's research and development in China, the initiation events analysis and evaluation was increasingly important. The research could be developed from the PWR analysis theories and methods. Based on the TMSR's design, the theories and methods of its initiation events analysis could be researched and developed. The initiation events lists and analysis methods of the two or three generation PWR, high-temperature gascooled reactor and sodium-cooled fast reactor were summarized. Based on the TMSR's design, its initiation events would be discussed and developed by the logical analysis. The analysis of TMSR's initiation events was preliminary studied and described. The research was important to clarify the events analysis rules, and useful to TMSR's designs and nuclear safety analysis. (authors)

  5. Event analysis in a primary substation

    Energy Technology Data Exchange (ETDEWEB)

    Jaerventausta, P; Paulasaari, H [Tampere Univ. of Technology (Finland); Partanen, J [Lappeenranta Univ. of Technology (Finland)

    1998-08-01

    The target of the project was to develop applications which observe the functions of a protection system by using modern microprocessor based relays. Microprocessor based relays have three essential capabilities: communication with the SCADA, the internal clock to produce time stamped event data, and the capability to register certain values during the fault. Using the above features some new functions for event analysis were developed in the project

  6. ES-RBE Event sequence reliability Benchmark exercise

    International Nuclear Information System (INIS)

    Poucet, A.E.J.

    1991-01-01

    The event Sequence Reliability Benchmark Exercise (ES-RBE) can be considered as a logical extension of the other three Reliability Benchmark Exercices : the RBE on Systems Analysis, the RBE on Common Cause Failures and the RBE on Human Factors. The latter, constituting Activity No. 1, was concluded by the end of 1987. The ES-RBE covered the techniques that are currently used for analysing and quantifying sequences of events starting from an initiating event to various plant damage states, including analysis of various system failures and/or successes, human intervention failure and/or success and dependencies between systems. By this way, one of the scopes of the ES-RBE was to integrate the experiences gained in the previous exercises

  7. Anatomy of event and human performance management in nuclear power plants

    International Nuclear Information System (INIS)

    Wang Jinhua

    2014-01-01

    This article analyzes the occurrence mechanism of events in nuclear power plants, and explains the four factors of human errors and the relations among them, then probes into the occurrence mechanism and characteristics of human errors in nuclear power plants. Moreover, the article clarifies that the principle of human performance training in nuclear power plants is all-member training, and that the implementation approach is to develop different human performance tools for different staff categories as workers, knowledge workers and supervisors, which are categorized based on characteristics of work of different staff. (author)

  8. The performance shaping factors influence analysis on the human reliability for NPP operation

    International Nuclear Information System (INIS)

    Farcasiu, M.; Nitoi, M.; Apostol, M.; Florescu, G.

    2008-01-01

    The Human Reliability Analysis (HRA) is an important step in Probabilistic Safety Assessment (PSA) studies and offers an advisability for concrete improvement of the man - machine - organization interfaces, reliability and safety. The goals of this analysis are to obtain sufficient details in order to understand and document all-important factors that affect human performance. The purpose of this paper is to estimate the human errors probabilities in view of the negative or positive effect of the human performance shaping factors (PSFs) for the mitigation of the initiating events which could occur in Nuclear Power Plant (NPP). Using THERP and SPAR-H methods, an analysis model of PSFs influence on the human reliability is performed. This model is applied to more important activities, that are necessary to mitigate 'one steam generator tube failure' event at Cernavoda NPP. The results are joint human error probabilities (JHEP) values estimated for the following situations: without regarding to PSFs influence; with PSFs in specific conditions; with PSFs which could have only positive influence and with PSFs which could have only negative influence. In addition, PSFs with negative influence were identified and using the DOE method, the necessary activities for changing negative influence were assigned. (authors)

  9. Analysis of Employee's Survey for Preventing Human-Errors

    International Nuclear Information System (INIS)

    Sung, Chanho; Kim, Younggab; Joung, Sanghoun

    2013-01-01

    Human errors in nuclear power plant can cause large and small events or incidents. These events or incidents are one of main contributors of reactor trip and might threaten the safety of nuclear plants. To prevent human-errors, KHNP(nuclear power plants) introduced 'Human-error prevention techniques' and have applied the techniques to main parts such as plant operation, operation support, and maintenance and engineering. This paper proposes the methods to prevent and reduce human-errors in nuclear power plants through analyzing survey results which includes the utilization of the human-error prevention techniques and the employees' awareness of preventing human-errors. With regard to human-error prevention, this survey analysis presented the status of the human-error prevention techniques and the employees' awareness of preventing human-errors. Employees' understanding and utilization of the techniques was generally high and training level of employee and training effect on actual works were in good condition. Also, employees answered that the root causes of human-error were due to working environment including tight process, manpower shortage, and excessive mission rather than personal negligence or lack of personal knowledge. Consideration of working environment is certainly needed. At the present time, based on analyzing this survey, the best methods of preventing human-error are personal equipment, training/education substantiality, private mental health check before starting work, prohibit of multiple task performing, compliance with procedures, and enhancement of job site review. However, the most important and basic things for preventing human-error are interests of workers and organizational atmosphere such as communication between managers and workers, and communication between employees and bosses

  10. Data analysis of event tape and connection

    International Nuclear Information System (INIS)

    Gong Huili

    1995-01-01

    The data analysis on the VAX-11/780 computer is briefly described, the data is from the recorded event tape of JUHU data acquisition system on the PDP-11/44 computer. The connection of the recorded event tapes of the XSYS data acquisition system on VAX computer is also introduced

  11. ANALYSIS OF EVENT TOURISM IN RUSSIA, ITS FUNCTIONS, WAYS TO IMPROVE THE EFFICIENCY OF EVENT

    Directory of Open Access Journals (Sweden)

    Mikhail Yur'evich Grushin

    2016-01-01

    Full Text Available This article considers one of the important directions of development of the national economy in the area of tourist services – development of event tourism in the Russian Federation. Today the market of event management in Russia is in the process of formation, therefore its impact on the socio-economic development of regions and Russia as a whole is minimal, and the analysis of the influence is not performed. This problem comes to the fore in the regions of Russia, specializing in the creation of event-direction tourist-recreational cluster. The article provides an analysis of the existing market of event management and event tourism functions. Providing the ways to improve the efficiency of event management and recommendations for the organizer of events in the regions. The article shows the specific role of event tourism in the national tourism and provides direction for the development of organizational and methodical recommendations on its formation in the regions of Russia and the creation of an effective management system at the regional level. The purpose of this article is to analyze the emerging in Russia event tourism market and its specifics. On the basis of these studies are considered folding patterns of the new market and the assessment of its impact on the modern national tourism industry. Methodology. To complete this article are used comparative and economic and statistical analysis methods. Conclusions/significance. The practical importance of this article is in the elimination of existing in the national tourism industry contradictions: on the one hand, in the Russian Federation is annually held a large amount events activities, including world-class in all regions say about tourist trips to the event, but the event tourism does not exist yet. In all regions, there is an internal and inbound tourism, but it has nothing to do with the event tourism. The article has a practical conclusions demonstrate the need to adapt the

  12. Models and data requirements for human reliability analysis

    International Nuclear Information System (INIS)

    1989-03-01

    It has been widely recognised for many years that the safety of the nuclear power generation depends heavily on the human factors related to plant operation. This has been confirmed by the accidents at Three Mile Island and Chernobyl. Both these cases revealed how human actions can defeat engineered safeguards and the need for special operator training to cover the possibility of unexpected plant conditions. The importance of the human factor also stands out in the analysis of abnormal events and insights from probabilistic safety assessments (PSA's), which reveal a large proportion of cases having their origin in faulty operator performance. A consultants' meeting, organized jointly by the International Atomic Energy Agency (IAEA) and the International Institute for Applied Systems Analysis (IIASA) was held at IIASA in Laxenburg, Austria, December 7-11, 1987, with the aim of reviewing existing models used in Probabilistic Safety Assessment (PSA) for Human Reliability Analysis (HRA) and of identifying the data required. The report collects both the contributions offered by the members of the Expert Task Force and the findings of the extensive discussions that took place during the meeting. Refs, figs and tabs

  13. Repeated Time-to-event Analysis of Consecutive Analgesic Events in Postoperative Pain

    DEFF Research Database (Denmark)

    Juul, Rasmus Vestergaard; Rasmussen, Sten; Kreilgaard, Mads

    2015-01-01

    BACKGROUND: Reduction in consumption of opioid rescue medication is often used as an endpoint when investigating analgesic efficacy of drugs by adjunct treatment, but appropriate methods are needed to analyze analgesic consumption in time. Repeated time-to-event (RTTE) modeling is proposed as a way...... to describe analgesic consumption by analyzing the timing of consecutive analgesic events. METHODS: Retrospective data were obtained from 63 patients receiving standard analgesic treatment including morphine on request after surgery following hip fracture. Times of analgesic events up to 96 h after surgery...... were extracted from hospital medical records. Parametric RTTE analysis was performed with exponential, Weibull, or Gompertz distribution of analgesic events using NONMEM®, version 7.2 (ICON Development Solutions, USA). The potential influences of night versus day, sex, and age were investigated...

  14. A study of the recovery from 120 events

    International Nuclear Information System (INIS)

    Baumont, Genevieve; Menage, F.; Bigot, F.

    1998-01-01

    The author reports a study which aimed at providing additional information for improving safety by using event analysis. The approach concentrates on the dynamics of error detection and the way errors and shortcomings are managed. The study is based on a systematic analysis of 120 events in nuclear power plants. The authors first outline the differences between the activities described in significant events and that which is assumed to take place during event and accident situations. They describe the methods used to transpose human reliability PSA model to event analysis, report the analysis (event selection, data studied during event analysis, types of errors). Studies concern events during power operation or plant outage. Results are analyzed in terms of number of events, percentage of error type, percentage of activation of engineered safety features before operators recovered the situation. They comment who recovers the error and how it is recovered, and more precisely discuss the case of multiple error situations

  15. Computer-aided event tree analysis by the impact vector method

    International Nuclear Information System (INIS)

    Lima, J.E.P.

    1984-01-01

    In the development of the Probabilistic Risk Analysis of Angra I, the ' large event tree/small fault tree' approach was adopted for the analysis of the plant behavior in an emergency situation. In this work, the event tree methodology is presented along with the adaptations which had to be made in order to attain a correct description of the safety system performances according to the selected analysis method. The problems appearing in the application of the methodology and their respective solutions are presented and discussed, with special emphasis to the impact vector technique. A description of the ETAP code ('Event Tree Analysis Program') developed for constructing and quantifying event trees is also given in this work. A preliminary version of the small-break LOCA analysis for Angra 1 is presented as an example of application of the methodology and of the code. It is shown that the use of the ETAP code sigmnificantly contributes to decreasing the time spent in event tree analyses, making it viable the practical application of the analysis approach referred above. (author) [pt

  16. ATHEANA: A Technique for Human Error Analysis: An Overview of Its Methodological Basis

    International Nuclear Information System (INIS)

    Wreathall, John; Ramey-Smith, Ann

    1998-01-01

    The U.S. NRC has developed a new human reliability analysis (HRA) method, called A Technique for Human Event Analysis (ATHEANA), to provide a way of modeling the so-called 'errors of commission' - that is, situations in which operators terminate or disable engineered safety features (ESFs) or similar equipment during accident conditions, thereby putting the plant at an increased risk of core damage. In its reviews of operational events, NRC has found that these errors of commission occur with a relatively high frequency (as high as 2 or 3 per year), but are noticeably missing from the scope of most current probabilistic risk assessments (PRAs). This new method was developed through a formalized approach that describes what can occur when operators behave rationally but have inadequate knowledge or poor judgement. In particular, the method is based on models of decision-making and response planning that have been used extensively in the aviation field, and on the analysis of major accidents in both the nuclear and non-nuclear fields. Other papers at this conference present summaries of these event analyses in both the nuclear and non-nuclear fields. This paper presents an overview of ATHEANA and summarizes how the method structures the analysis of operationally significant events, and helps HRA analysts identify and model potentially risk-significant errors of commission in plant PRAs. (authors)

  17. Trending analysis of precursor events

    International Nuclear Information System (INIS)

    Watanabe, Norio

    1998-01-01

    The Accident Sequence Precursor (ASP) Program of United States Nuclear Regulatory Commission (U.S.NRC) identifies and categorizes operational events at nuclear power plants in terms of the potential for core damage. The ASP analysis has been performed on yearly basis and the results have been published in the annual reports. This paper describes the trends in initiating events and dominant sequences for 459 precursors identified in the ASP Program during the 1969-94 period and also discusses a comparison with dominant sequences predicted in the past Probabilistic Risk Assessment (PRA) studies. These trends were examined for three time periods, 1969-81, 1984-87 and 1988-94. Although the different models had been used in the ASP analyses for these three periods, the distribution of precursors by dominant sequences show similar trends to each other. For example, the sequences involving loss of both main and auxiliary feedwater were identified in many PWR events and those involving loss of both high and low coolant injection were found in many BWR events. Also, it was found that these dominant sequences were comparable to those determined to be dominant in the predictions by the past PRAs. As well, a list of the 459 precursors identified are provided in Appendix, indicating initiating event types, unavailable systems, dominant sequences, conditional core damage probabilities, and so on. (author)

  18. Estimating the response times of human operators working in the main control room of nuclear power plants based on the context of a seismic event – A case study

    International Nuclear Information System (INIS)

    Park, Jinkyun; Kim, Yochan; Kim, Jung Han; Jung, Wondea; Jang, Seung Cheol

    2015-01-01

    Highlights: • Response times under seismic events are necessary for human reliability analysis. • Conceptual framework to estimate response times under a seismic event is suggested. • Four kinds of representative contexts in seismic events are considered. • Rules for estimating response times on the representative contexts are extracted. - Abstract: After the Fukushima accident, a couple of novel issues have raised in terms of the safety assessment of nuclear power plants (NPPs). This means that the performance of human operators should be properly evaluated under an extreme event. However, it is unrealistic to collect a sufficient amount of human performance data from a real event, such as a great earthquake. As one of the promising solutions, a conceptual framework is suggested in this paper, which is helpful for estimating the response time data of human operators working in the main control room of NPPs under a seismic event. To this end, the four kinds of representative contexts that could be anticipated from seismic events are identified. Then the response times of human operators who are faced with similar contexts are reviewed from existing literatures and databases. As a result, a couple of rules that allow us to extrapolate the response times of human operators under seismic events are extracted. Although underlying rationales being used for determining these rules are still arguable, it is expected that response times under seismic events could be properly understood along with accumulating those of human operators against non-seismic conditions

  19. A code for simulation of human failure events in nuclear power plants: SIMPROC

    International Nuclear Information System (INIS)

    Gil, Jesus; Fernandez, Ivan; Murcia, Santiago; Gomez, Javier; Marrao, Hugo; Queral, Cesar; Exposito, Antonio; Rodriguez, Gabriel; Ibanez, Luisa; Hortal, Javier; Izquierdo, Jose M.; Sanchez, Miguel; Melendez, Enrique

    2011-01-01

    Over the past years, many Nuclear Power Plant organizations have performed Probabilistic Safety Assessments to identify and understand key plant vulnerabilities. As part of enhancing the PSA quality, the Human Reliability Analysis is essential to make a realistic evaluation of safety and about the potential facility's weaknesses. Moreover, it has to be noted that HRA continues to be a large source of uncertainty in the PSAs. Within their current joint collaborative activities, Indizen, Universidad Politecnica de Madrid and Consejo de Seguridad Nuclear have developed the so-called SIMulator of PROCedures (SIMPROC), a tool aiming at simulate events related with human actions and able to interact with a plant simulation model. The tool helps the analyst to quantify the importance of human actions in the final plant state. Among others, the main goal of SIMPROC is to check the Emergency Operating Procedures being used by operating crew in order to lead the plant to a safe shutdown plant state. Currently SIMPROC is coupled with the SCAIS software package, but the tool is flexible enough to be linked to other plant simulation codes. SIMPROC-SCAIS applications are shown in the present article to illustrate the tool performance. The applications were developed in the framework of the Nuclear Energy Agency project on Safety Margin Assessment and Applications (SM2A). First an introductory example was performed to obtain the damage domain boundary of a selected sequence from a SBLOCA. Secondly, the damage domain area of a selected sequence from a loss of Component Cooling Water with a subsequent seal LOCA was calculated. SIMPROC simulates the corresponding human actions in both cases. The results achieved shown how the system can be adapted to a wide range of purposes such as Dynamic Event Tree delineation, Emergency Operating Procedures and damage domain search.

  20. A joint analysis of wave and surge conditions for past and present extrem events in the south-western Baltic Sea

    Science.gov (United States)

    Groll, Nikolaus; Gaslikova, Lidia

    2017-04-01

    Extreme marine events in the south-western Baltic Sea like the historic storm in 1872 are rare, but have large impacts on human safety and coastal infrastructure. The aforementioned extreme storm event of 1872 and has cost over 250 human lives, left severely damaged infrastructure and caused land loss due to coastal erosion. Recent extreme events also result in drastic impacts to coastal regions. Using results from numerical wave and hydrodynamic model simulations we will present a joint analysis of wave and water level conditions for selected extreme events. For the historic event the numerical models have been forced by reconstructed wind and pressure fields from pressure readings. Simulated atmospheric conditions from reanalysis have been used for the more recent events. The height of the water level due to the possible previous inflow of water masses in the Baltic Sea basin, as well as possible seiches and swell effects have been incorporated in the simulations. We will discuss similarities and differences between the historic and the more recent marine hazard events.

  1. Inclusion of task dependence in human reliability analysis

    International Nuclear Information System (INIS)

    Su, Xiaoyan; Mahadevan, Sankaran; Xu, Peida; Deng, Yong

    2014-01-01

    Dependence assessment among human errors in human reliability analysis (HRA) is an important issue, which includes the evaluation of the dependence among human tasks and the effect of the dependence on the final human error probability (HEP). This paper represents a computational model to handle dependence in human reliability analysis. The aim of the study is to automatically provide conclusions on the overall degree of dependence and calculate the conditional human error probability (CHEP) once the judgments of the input factors are given. The dependence influencing factors are first identified by the experts and the priorities of these factors are also taken into consideration. Anchors and qualitative labels are provided as guidance for the HRA analyst's judgment of the input factors. The overall degree of dependence between human failure events is calculated based on the input values and the weights of the input factors. Finally, the CHEP is obtained according to a computing formula derived from the technique for human error rate prediction (THERP) method. The proposed method is able to quantify the subjective judgment from the experts and improve the transparency in the HEP evaluation process. Two examples are illustrated to show the effectiveness and the flexibility of the proposed method. - Highlights: • We propose a computational model to handle dependence in human reliability analysis. • The priorities of the dependence influencing factors are taken into consideration. • The overall dependence degree is determined by input judgments and the weights of factors. • The CHEP is obtained according to a computing formula derived from THERP

  2. Extreme flood event analysis in Indonesia based on rainfall intensity and recharge capacity

    Science.gov (United States)

    Narulita, Ida; Ningrum, Widya

    2018-02-01

    Indonesia is very vulnerable to flood disaster because it has high rainfall events throughout the year. Flood is categorized as the most important hazard disaster because it is causing social, economic and human losses. The purpose of this study is to analyze extreme flood event based on satellite rainfall dataset to understand the rainfall characteristic (rainfall intensity, rainfall pattern, etc.) that happened before flood disaster in the area for monsoonal, equatorial and local rainfall types. Recharge capacity will be analyzed using land cover and soil distribution. The data used in this study are CHIRPS rainfall satellite data on 0.05 ° spatial resolution and daily temporal resolution, and GSMap satellite rainfall dataset operated by JAXA on 1-hour temporal resolution and 0.1 ° spatial resolution, land use and soil distribution map for recharge capacity analysis. The rainfall characteristic before flooding, and recharge capacity analysis are expected to become the important information for flood mitigation in Indonesia.

  3. Performance Analysis: Work Control Events Identified January - August 2010

    Energy Technology Data Exchange (ETDEWEB)

    De Grange, C E; Freeman, J W; Kerr, C E; Holman, G; Marsh, K; Beach, R

    2011-01-14

    This performance analysis evaluated 24 events that occurred at LLNL from January through August 2010. The analysis identified areas of potential work control process and/or implementation weaknesses and several common underlying causes. Human performance improvement and safety culture factors were part of the causal analysis of each event and were analyzed. The collective significance of all events in 2010, as measured by the occurrence reporting significance category and by the proportion of events that have been reported to the DOE ORPS under the ''management concerns'' reporting criteria, does not appear to have increased in 2010. The frequency of reporting in each of the significance categories has not changed in 2010 compared to the previous four years. There is no change indicating a trend in the significance category and there has been no increase in the proportion of occurrences reported in the higher significance category. Also, the frequency of events, 42 events reported through August 2010, is not greater than in previous years and is below the average of 63 occurrences per year at LLNL since 2006. Over the previous four years, an average of 43% of the LLNL's reported occurrences have been reported as either ''management concerns'' or ''near misses.'' In 2010, 29% of the occurrences have been reported as ''management concerns'' or ''near misses.'' This rate indicates that LLNL is now reporting fewer ''management concern'' and ''near miss'' occurrences compared to the previous four years. From 2008 to the present, LLNL senior management has undertaken a series of initiatives to strengthen the work planning and control system with the primary objective to improve worker safety. In 2008, the LLNL Deputy Director established the Work Control Integrated Project Team to develop the core requirements and graded

  4. Development of Human Performance Analysis and Advanced HRA Methodology

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Won Dea; Park, Jin Kyun; Kim, Jae Whan; Kim, Seong Whan; Kim, Man Cheol; Ha, Je Joo

    2007-06-15

    The purpose of this project is to build a systematic framework that can evaluate the effect of human factors related problems on the safety of nuclear power plants (NPPs) as well as develop a technology that can be used to enhance human performance. The research goal of this project is twofold: (1) the development of a human performance database and a framework to enhance human performance, and (2) the analysis of human error with constructing technical basis for human reliability analysis. There are three kinds of main results of this study. The first result is the development of a human performance database, called OPERA-I/II (Operator Performance and Reliability Analysis, Part I and Part II). In addition, a standard communication protocol was developed based on OPERA to reduce human error caused from communication error in the phase of event diagnosis. Task complexity (TACOM) measure and the methodology of optimizing diagnosis procedures were also finalized during this research phase. The second main result is the development of a software, K-HRA, which is to support the standard HRA method. Finally, an advanced HRA method named as AGAPE-ET was developed by combining methods MDTA (misdiagnosis tree analysis technique) and K-HRA, which can be used to analyze EOC (errors of commission) and EOO (errors of ommission). These research results, such as OPERA-I/II, TACOM, a standard communication protocol, K-HRA and AGAPE-ET methods will be used to improve the quality of HRA and to enhance human performance in nuclear power plants.

  5. Development of Human Performance Analysis and Advanced HRA Methodology

    International Nuclear Information System (INIS)

    Jung, Won Dea; Park, Jin Kyun; Kim, Jae Whan; Kim, Seong Whan; Kim, Man Cheol; Ha, Je Joo

    2007-06-01

    The purpose of this project is to build a systematic framework that can evaluate the effect of human factors related problems on the safety of nuclear power plants (NPPs) as well as develop a technology that can be used to enhance human performance. The research goal of this project is twofold: (1) the development of a human performance database and a framework to enhance human performance, and (2) the analysis of human error with constructing technical basis for human reliability analysis. There are three kinds of main results of this study. The first result is the development of a human performance database, called OPERA-I/II (Operator Performance and Reliability Analysis, Part I and Part II). In addition, a standard communication protocol was developed based on OPERA to reduce human error caused from communication error in the phase of event diagnosis. Task complexity (TACOM) measure and the methodology of optimizing diagnosis procedures were also finalized during this research phase. The second main result is the development of a software, K-HRA, which is to support the standard HRA method. Finally, an advanced HRA method named as AGAPE-ET was developed by combining methods MDTA (misdiagnosis tree analysis technique) and K-HRA, which can be used to analyze EOC (errors of commission) and EOO (errors of ommission). These research results, such as OPERA-I/II, TACOM, a standard communication protocol, K-HRA and AGAPE-ET methods will be used to improve the quality of HRA and to enhance human performance in nuclear power plants

  6. Fukushima Daiichi - Human and organizational facts - Part 1: The events and the organizations which worked in controlling the incident

    International Nuclear Information System (INIS)

    2012-01-01

    After the Fukushima Daiichi accident on March 11 th , 2011, the Swiss Federal Nuclear Safety Inspectorate (ENSI) conducted various analyses in order to understand the sequence of events and the contributing factors from both a human as well as an organizational point of view. This analysis considers reports published by TEPCO, the operator of the Fukushima power plants, the Japanese Authorities and IAEA. The deepening of the analysis of the human and organizational aspects became necessary as the accident and its causes are very complex. This complexity is not only the result of technical aspects, but it is also due to the interactions between technical, organizational and human aspects. It is to be considered that additional analyses will be required to exactly understand the physical, organizational and human processes involved. One has to keep in mind the tremendous dimension of the earthquake and the tsunami, as well as the courage and devotedness shown by the actors involved, especially the workers of the Fukushima plants. They had to treat the dramatic issues of the accident, which hit three reactor blocks, and they had to react on the spot to the catastrophic situation with many subsequent earthquakes and, sometimes, without news about their own families. It is necessary to understand the organizational weaknesses with respect to the protection of the plant against the danger of a very large tsunami and the management of a serious accident, in order to learn the necessary lessons. The weaknesses can only be explained by a thorough analysis of the situation which, at the same time, takes the technical environment into account as well as organizational aspects of the accident. The present report considers important event data which are necessary for the understanding of the situation that the various organizations and persons had to master. The role of the organizations in Tokyo and in the Fukushima prefecture is also analyzed. The Fukushima accident is the

  7. A human factors experiment on the event-paced control tasks issue

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyun Chul; Park, Jae Chang; Oh, In Seok; Lee, Jung Woon; Lee, Ki Young; Park, Jong Kyun [Korea Atomic Energy Research Institute, Taejeon (Korea)

    2000-03-01

    KEPRI(Korea Electric Power Research Institute) requires human factors validation tests according to the progress of the KNGR MMI design. This report describes the experimental results of an human factors validation issue, Event-Paced Control Tasks issue. The Event-Paced Control Task issue is to test that the designed MMI shall support operators in performing control tasks in pace with the plant dynamics. Task completion time and successful execution are defined as performance measures on the issue. Through an experiment on the issue with 3 scenarios and 5 subjects, we report that the variation of task completion time between subjects has a narrow band for each scenarios, however two among the total 15 experimental runs result in the failure that subject does not reach to the predefined operational goal. Incorrect operational strategy, insufficient training, and MMI design discrepancies are inferred as the causes of the failures. However these experimental results don't indicate the close of the Event-Paced Control Tasks issue. The validation test results under the experimental environment composed of the partial MMI representations, an unstable simulator, and insufficient subject training, are significant in the limited conditions. Thus, for the purpose of the complete issue close, the validation test on the Event-Paced Control Tasks issue should be repeatedly carried out in pace with the performance improvement of the experimental environment. 13 figs., 4 tabs. (Author)

  8. Serious adverse events with infliximab: analysis of spontaneously reported adverse events.

    Science.gov (United States)

    Hansen, Richard A; Gartlehner, Gerald; Powell, Gregory E; Sandler, Robert S

    2007-06-01

    Serious adverse events such as bowel obstruction, heart failure, infection, lymphoma, and neuropathy have been reported with infliximab. The aims of this study were to explore adverse event signals with infliximab by using a long period of post-marketing experience, stratifying by indication. The relative reporting of infliximab adverse events to the U.S. Food and Drug Administration (FDA) was assessed with the public release version of the adverse event reporting system (AERS) database from 1968 to third quarter 2005. On the basis of a systematic review of adverse events, Medical Dictionary for Regulatory Activities (MedDRA) terms were mapped to predefined categories of adverse events, including death, heart failure, hepatitis, infection, infusion reaction, lymphoma, myelosuppression, neuropathy, and obstruction. Disproportionality analysis was used to calculate the empiric Bayes geometric mean (EBGM) and corresponding 90% confidence intervals (EB05, EB95) for adverse event categories. Infliximab was identified as the suspect medication in 18,220 reports in the FDA AERS database. We identified a signal for lymphoma (EB05 = 6.9), neuropathy (EB05 = 3.8), infection (EB05 = 2.9), and bowel obstruction (EB05 = 2.8). The signal for granulomatous infections was stronger than the signal for non-granulomatous infections (EB05 = 12.6 and 2.4, respectively). The signals for bowel obstruction and infusion reaction were specific to patients with IBD; this suggests potential confounding by indication, especially for bowel obstruction. In light of this additional evidence of risk of lymphoma, neuropathy, and granulomatous infections, clinicians should stress this risk in the shared decision-making process.

  9. Human performance analysis in the frame of probabilistic safety assessment of research reactors

    International Nuclear Information System (INIS)

    Farcasiu, Mita; Nitoi, Mirela; Apostol, Minodora; Turcu, I.; Florescu, Gh.

    2005-01-01

    Full text: The analysis of operating experience has identified the importance of human performance in reliability and safety of research reactors. In Probabilistic Safety Assessment (PSA) of nuclear facilities, human performance analysis (HPA) is used in order to estimate human error contribution to the failure of system components or functions. HPA is a qualitative and quantitative analysis of human actions identified for error-likely situations or accident-prone situations. Qualitative analysis is used to identify all man-machine interfaces that can lead to an accident, types of human interactions which may mitigate or exacerbate the accident, types of human errors and performance shaping factors. Quantitative analysis is used to develop estimates of human error probability as effects of human performance in reliability and safety. The goal of this paper is to accomplish a HPA in the PSA frame for research reactors. Human error probabilities estimated as results of human actions analysis could be included in system event tree and/or system fault tree. The achieved sensitivity analyses determine human performance sensibility at systematically variations both for dependencies level between human actions and for operator stress level. The necessary information was obtained from operating experience of research reactor TRIGA from INR Pitesti. The required data were obtained from generic data bases. (authors)

  10. Multi-Unit Initiating Event Analysis for a Single-Unit Internal Events Level 1 PSA

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dong San; Park, Jin Hee; Lim, Ho Gon [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The Fukushima nuclear accident in 2011 highlighted the importance of considering the risks from multi-unit accidents at a site. The ASME/ANS probabilistic risk assessment (PRA) standard also includes some requirements related to multi-unit aspects, one of which (IE-B5) is as follows: 'For multi-unit sites with shared systems, DO NOT SUBSUME multi-unit initiating events if they impact mitigation capability [1].' However, the existing single-unit PSA models do not explicitly consider multi-unit initiating events and hence systems shared by multiple units (e.g., alternate AC diesel generator) are fully credited for the single unit and ignores the need for the shared systems by other units at the same site [2]. This paper describes the results of the multi-unit initiating event (IE) analysis performed as a part of the at-power internal events Level 1 probabilistic safety assessment (PSA) for an OPR1000 single unit ('reference unit'). In this study, a multi-unit initiating event analysis for a single-unit PSA was performed, and using the results, dual-unit LOOP initiating event was added to the existing PSA model for the reference unit (OPR1000 type). Event trees were developed for dual-unit LOOP and dual-unit SBO which can be transferred from dual- unit LOOP. Moreover, CCF basic events for 5 diesel generators were modelled. In case of simultaneous SBO occurrences in both units, this study compared two different assumptions on the availability of the AAC D/G. As a result, when dual-unit LOOP initiating event was added to the existing single-unit PSA model, the total CDF increased by 1∼ 2% depending on the probability that the AAC D/G is available to a specific unit in case of simultaneous SBO in both units.

  11. Climate Central World Weather Attribution (WWA) project: Real-time extreme weather event attribution analysis

    Science.gov (United States)

    Haustein, Karsten; Otto, Friederike; Uhe, Peter; Allen, Myles; Cullen, Heidi

    2015-04-01

    Extreme weather detection and attribution analysis has emerged as a core theme in climate science over the last decade or so. By using a combination of observational data and climate models it is possible to identify the role of climate change in certain types of extreme weather events such as sea level rise and its contribution to storm surges, extreme heat events and droughts or heavy rainfall and flood events. These analyses are usually carried out after an extreme event has occurred when reanalysis and observational data become available. The Climate Central WWA project will exploit the increasing forecast skill of seasonal forecast prediction systems such as the UK MetOffice GloSea5 (Global seasonal forecasting system) ensemble forecasting method. This way, the current weather can be fed into climate models to simulate large ensembles of possible weather scenarios before an event has fully emerged yet. This effort runs along parallel and intersecting tracks of science and communications that involve research, message development and testing, staged socialization of attribution science with key audiences, and dissemination. The method we employ uses a very large ensemble of simulations of regional climate models to run two different analyses: one to represent the current climate as it was observed, and one to represent the same events in the world that might have been without human-induced climate change. For the weather "as observed" experiment, the atmospheric model uses observed sea surface temperature (SST) data from GloSea5 (currently) and present-day atmospheric gas concentrations to simulate weather events that are possible given the observed climate conditions. The weather in the "world that might have been" experiments is obtained by removing the anthropogenic forcing from the observed SSTs, thereby simulating a counterfactual world without human activity. The anthropogenic forcing is obtained by comparing the CMIP5 historical and natural simulations

  12. Trend analysis and comparison of operators' human error events occurred at overseas and domestic nuclear power plants

    International Nuclear Information System (INIS)

    Takagawa, Kenichi

    2006-01-01

    Human errors by operators at overseas and domestic nuclear power plants during the period from 2002 to 2005 were compared and their trends analyzed. The most frequently cited cause of such errors was 'insufficient team monitoring' (inadequate superiors' and other crews' instructions and supervision) both at overseas and domestic plants, followed by 'insufficient self-checking' (lack of cautions by the operator himself). A comparison of the effects of the errors on the operations of plants in Japan and the United Sates showed that the drop in plant output and plant shutdowns at plants in Japan were approximately one-tenth of those in the United States. The ratio of automatic reactor trips to the total number of human errors reported is about 6% for both Japanese and American plants. Looking at changes in the incidence of human errors by years of occurrence, although a distinctive trend cannot be identified for domestic nuclear power plants due to insufficient reported cases, 'inadequate self-checking' as a factor contributing to human errors at overseas nuclear power plants has decreased significantly over the past four years. Regarding changes in the effects of human errors on the operations of plants during the four-year period, events leading to an automatic reactor trip have tended to increase at American plants. Conceivable factors behind this increasing tendency included lack of operating experience by a team (e.g., plant transients and reactor shutdowns and startups) and excessive dependence on training simulators. (author)

  13. A framework of dynamic analysis for risks asociated with human activity at radioactive waste disposal sites

    International Nuclear Information System (INIS)

    Umeki, H.; Masuda, S.

    1989-01-01

    Human intrusive actions at radioactive waste disposal sites which cause radiological impact were identified in connection with other events and processes on the influence diagram. The scenarios of less likely events including human intrusive actions were generated from the diagram and then treated by probabilistic way. For assigning probabilities of events dynamically, simultaneous difference equations were introduced and simple general solutions which satisfy the equations were used to illustrate the example calculations for both direct and indirect impacts by human intrusive actions such as drilling/mining and pumping of groundwater. The method developed here will be useful for both scenario screening in overall scenario study and risk calculation combined with consequence analysis

  14. Enhancing the Effectiveness of Significant Event Analysis: Exploring Personal Impact and Applying Systems Thinking in Primary Care.

    Science.gov (United States)

    Bowie, Paul; McNaughton, Elaine; Bruce, David; Holly, Deirdre; Forrest, Eleanor; Macleod, Marion; Kennedy, Susan; Power, Ailsa; Toppin, Denis; Black, Irene; Pooley, Janet; Taylor, Audrey; Swanson, Vivien; Kelly, Moya; Ferguson, Julie; Stirling, Suzanne; Wakeling, Judy; Inglis, Angela; McKay, John; Sargeant, Joan

    2016-01-01

    Significant event analysis (SEA) is well established in many primary care settings but can be poorly implemented. Reasons include the emotional impact on clinicians and limited knowledge of systems thinking in establishing why events happen and formulating improvements. To enhance SEA effectiveness, we developed and tested "guiding tools" based on human factors principles. Mixed-methods development of guiding tools (Personal Booklet-to help with emotional demands and apply a human factors analysis at the individual level; Desk Pad-to guide a team-based systems analysis; and a written Report Format) by a multiprofessional "expert" group and testing with Scottish primary care practitioners who submitted completed enhanced SEA reports. Evaluation data were collected through questionnaire, telephone interviews, and thematic analysis of SEA reports. Overall, 149/240 care practitioners tested the guiding tools and submitted completed SEA reports (62.1%). Reported understanding of how to undertake SEA improved postintervention (P systems issues (85/123, 69.1%), while most found the Report Format clear (94/123, 76.4%) and would recommend it (88/123, 71.5%). Most SEA reports adopted a systems approach to analyses (125/149, 83.9%), care improvement (74/149, 49.7), or planned actions (42/149, 28.2%). Applying human factors principles to SEA potentially enables care teams to gain a systems-based understanding of why things go wrong, which may help with related emotional demands and with more effective learning and improvement.

  15. Lessons-Learned from an Event during Overhaul

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jitae [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2013-05-15

    The event frequency, also including portion of human errors, has been decreasing compared to last ten years. However, events due to human errors during overhaul occur every year. From analyzed results for human-related events during overhaul, similar problems were identified. And organizational and safety cultural factors were also identified. On the other hand, another event during overhaul is analyzed and Lessons-Learned is drawn in an aspect of the operators' situation awareness. There was an event during overhaul and the analyzed results drawn Lessons-Learned in the aspect of the operators' situation awareness. From the analysis, several alarms and variation of plant parameters during overhaul can occur due to various maintenance works and tests. And in the aspect of the situation awareness, operators can miss, neglect, or not recognize the abnormal situation due to other maintenance activities occurring simultaneously. Therefore, countermeasures such as operator education or training, development of operator support systems, and further researches should be necessary to cope with these problems.

  16. Lessons-Learned from an Event during Overhaul

    International Nuclear Information System (INIS)

    Kim, Jitae

    2013-01-01

    The event frequency, also including portion of human errors, has been decreasing compared to last ten years. However, events due to human errors during overhaul occur every year. From analyzed results for human-related events during overhaul, similar problems were identified. And organizational and safety cultural factors were also identified. On the other hand, another event during overhaul is analyzed and Lessons-Learned is drawn in an aspect of the operators' situation awareness. There was an event during overhaul and the analyzed results drawn Lessons-Learned in the aspect of the operators' situation awareness. From the analysis, several alarms and variation of plant parameters during overhaul can occur due to various maintenance works and tests. And in the aspect of the situation awareness, operators can miss, neglect, or not recognize the abnormal situation due to other maintenance activities occurring simultaneously. Therefore, countermeasures such as operator education or training, development of operator support systems, and further researches should be necessary to cope with these problems

  17. System risk evolution analysis and risk critical event identification based on event sequence diagram

    International Nuclear Information System (INIS)

    Luo, Pengcheng; Hu, Yang

    2013-01-01

    During system operation, the environmental, operational and usage conditions are time-varying, which causes the fluctuations of the system state variables (SSVs). These fluctuations change the accidents’ probabilities and then result in the system risk evolution (SRE). This inherent relation makes it feasible to realize risk control by monitoring the SSVs in real time, herein, the quantitative analysis of SRE is essential. Besides, some events in the process of SRE are critical to system risk, because they act like the “demarcative points” of safety and accident, and this characteristic makes each of them a key point of risk control. Therefore, analysis of SRE and identification of risk critical events (RCEs) are remarkably meaningful to ensure the system to operate safely. In this context, an event sequence diagram (ESD) based method of SRE analysis and the related Monte Carlo solution are presented; RCE and risk sensitive variable (RSV) are defined, and the corresponding identification methods are also proposed. Finally, the proposed approaches are exemplified with an accident scenario of an aircraft getting into the icing region

  18. Construction and Updating of Event Models in Auditory Event Processing

    Science.gov (United States)

    Huff, Markus; Maurer, Annika E.; Brich, Irina; Pagenkopf, Anne; Wickelmaier, Florian; Papenmeier, Frank

    2018-01-01

    Humans segment the continuous stream of sensory information into distinct events at points of change. Between 2 events, humans perceive an event boundary. Present theories propose changes in the sensory information to trigger updating processes of the present event model. Increased encoding effort finally leads to a memory benefit at event…

  19. Basic Safety Considerations for Nuclear Power Plant Dealing with External Human Induced Events

    Energy Technology Data Exchange (ETDEWEB)

    Salem, W., E-mail: wafaasalem21@yahoo.com [Nuclear and Radiological Regulatory Authority (Egypt)

    2014-10-15

    Facilities and human activities in the region in which a nuclear power plant is located may under some conditions affect its safety. The potential sources of human induced events external to the plant should be identified and the severity of the possible resulting hazard phenomena should be evaluated to derive the appropriate design bases for the plant. They should also be monitored and periodically assessed over the lifetime of the plant to ensure that consistency with the design assumptions is maintained. External human induced events that could affect safety should be investigated in the site evaluation stage for every nuclear power plant site. The region is required to be examined for facilities and human activities that have the potential, under certain conditions, to endanger the nuclear power plant over its entire lifetime. Each relevant potential source is required to be identified and assessed to determine the potential interactions with personnel and plant items important to safety. (author)

  20. Analysis of Human Errors in Industrial Incidents and Accidents for Improvement of Work Safety

    DEFF Research Database (Denmark)

    Leplat, J.; Rasmussen, Jens

    1984-01-01

    Methods for the analysis of work accidents are discussed, and a description is given of the use of a causal situation analysis in terms of a 'variation tree' in order to explain the course of events of the individual cases and to identify possible improvements. The difficulties in identifying...... 'causes' of accidents are discussed, and it is proposed to analyze accident reports with the specific aim of identifying the potential for future improvements rather than causes of past events. In contrast to traditional statistical analysis of work accident data, which typically give very general...... recommendations, the method proposed identifies very explicit countermeasures. Improvements require a change in human decisions during equipment design, work planning, or the execution itself. The use of a model of human behavior drawing a distinction between automated skill-based behavior, rule-based 'know...

  1. Analysis of Paks NPP Personnel Activity during Safety Related Event Sequences

    International Nuclear Information System (INIS)

    Bareith, A.; Hollo, Elod; Karsa, Z.; Nagy, S.

    1998-01-01

    Within the AGNES Project (Advanced Generic and New Evaluation of Safety) the Level-1 PSA model of the Paks NPP Unit 3 was developed in form of a detailed event tree/fault tree structure (53 initiating events, 580 event sequences, 6300 basic events are involved). This model gives a good basis for quantitative evaluation of potential consequences of actually occurred safety-related events, i.e. for precursor event studies. To make these studies possible and efficient, the current qualitative event analysis practice should be reviewed and a new additional quantitative analysis procedure and system should be developed and applied. The present paper gives an overview of the method outlined for both qualitative and quantitative analyses of the operator crew activity during off-normal situations. First, the operator performance experienced during past operational events is discussed. Sources of raw information, the qualitative evaluation process, the follow-up actions, as well as the documentation requirements are described. Second, the general concept of the proposed precursor event analysis is described. Types of modeled interactions and the considered performance influences are presented. The quantification of the potential consequences of the identified precursor events is based on the task-oriented, Level-1 PSA model of the plant unit. A precursor analysis system covering the evaluation of operator activities is now under development. Preliminary results gained during a case study evaluation of a past historical event are presented. (authors)

  2. Dynamics of large-scale cortical interactions at high gamma frequencies during word production: event related causality (ERC) analysis of human electrocorticography (ECoG).

    Science.gov (United States)

    Korzeniewska, Anna; Franaszczuk, Piotr J; Crainiceanu, Ciprian M; Kuś, Rafał; Crone, Nathan E

    2011-06-15

    Intracranial EEG studies in humans have shown that functional brain activation in a variety of functional-anatomic domains of human cortex is associated with an increase in power at a broad range of high gamma (>60Hz) frequencies. Although these electrophysiological responses are highly specific for the location and timing of cortical processing and in animal recordings are highly correlated with increased population firing rates, there has been little direct empirical evidence for causal interactions between different recording sites at high gamma frequencies. Such causal interactions are hypothesized to occur during cognitive tasks that activate multiple brain regions. To determine whether such causal interactions occur at high gamma frequencies and to investigate their functional significance, we used event-related causality (ERC) analysis to estimate the dynamics, directionality, and magnitude of event-related causal interactions using subdural electrocorticography (ECoG) recorded during two word production tasks: picture naming and auditory word repetition. A clinical subject who had normal hearing but was skilled in American Signed Language (ASL) provided a unique opportunity to test our hypothesis with reference to a predictable pattern of causal interactions, i.e. that language cortex interacts with different areas of sensorimotor cortex during spoken vs. signed responses. Our ERC analyses confirmed this prediction. During word production with spoken responses, perisylvian language sites had prominent causal interactions with mouth/tongue areas of motor cortex, and when responses were gestured in sign language, the most prominent interactions involved hand and arm areas of motor cortex. Furthermore, we found that the sites from which the most numerous and prominent causal interactions originated, i.e. sites with a pattern of ERC "divergence", were also sites where high gamma power increases were most prominent and where electrocortical stimulation mapping

  3. A stochastic dynamic model for human error analysis in nuclear power plants

    Science.gov (United States)

    Delgado-Loperena, Dharma

    Nuclear disasters like Three Mile Island and Chernobyl indicate that human performance is a critical safety issue, sending a clear message about the need to include environmental press and competence aspects in research. This investigation was undertaken to serve as a roadmap for studying human behavior through the formulation of a general solution equation. The theoretical model integrates models from two heretofore-disassociated disciplines (behavior specialists and technical specialists), that historically have independently studied the nature of error and human behavior; including concepts derived from fractal and chaos theory; and suggests re-evaluation of base theory regarding human error. The results of this research were based on comprehensive analysis of patterns of error, with the omnipresent underlying structure of chaotic systems. The study of patterns lead to a dynamic formulation, serving for any other formula used to study human error consequences. The search for literature regarding error yielded insight for the need to include concepts rooted in chaos theory and strange attractors---heretofore unconsidered by mainstream researchers who investigated human error in nuclear power plants or those who employed the ecological model in their work. The study of patterns obtained from the rupture of a steam generator tube (SGTR) event simulation, provided a direct application to aspects of control room operations in nuclear power plant operations. In doing so, the conceptual foundation based in the understanding of the patterns of human error analysis can be gleaned, resulting in reduced and prevent undesirable events.

  4. Disruptive Event Biosphere Doser Conversion Factor Analysis

    Energy Technology Data Exchange (ETDEWEB)

    M. Wasiolek

    2000-12-28

    The purpose of this report was to document the process leading to, and the results of, development of radionuclide-, exposure scenario-, and ash thickness-specific Biosphere Dose Conversion Factors (BDCFs) for the postulated postclosure extrusive igneous event (volcanic eruption) at Yucca Mountain. BDCF calculations were done for seventeen radionuclides. The selection of radionuclides included those that may be significant dose contributors during the compliance period of up to 10,000 years, as well as radionuclides of importance for up to 1 million years postclosure. The approach documented in this report takes into account human exposure during three different phases at the time of, and after, volcanic eruption. Calculations of disruptive event BDCFs used the GENII-S computer code in a series of probabilistic realizations to propagate the uncertainties of input parameters into the output. The pathway analysis included consideration of different exposure pathway's contribution to the BDCFs. BDCFs for volcanic eruption, when combined with the concentration of radioactivity deposited by eruption on the soil surface, allow calculation of potential radiation doses to the receptor of interest. Calculation of radioactivity deposition is outside the scope of this report and so is the transport of contaminated ash from the volcano to the location of the receptor. The integration of the biosphere modeling results (BDCFs) with the outcomes of the other component models is accomplished in the Total System Performance Assessment (TSPA), in which doses are calculated to the receptor of interest from radionuclides postulated to be released to the environment from the potential repository at Yucca Mountain.

  5. Parallel processor for fast event analysis

    International Nuclear Information System (INIS)

    Hensley, D.C.

    1983-01-01

    Current maximum data rates from the Spin Spectrometer of approx. 5000 events/s (up to 1.3 MBytes/s) and minimum analysis requiring at least 3000 operations/event require a CPU cycle time near 70 ns. In order to achieve an effective cycle time of 70 ns, a parallel processing device is proposed where up to 4 independent processors will be implemented in parallel. The individual processors are designed around the Am2910 Microsequencer, the AM29116 μP, and the Am29517 Multiplier. Satellite histogramming in a mass memory system will be managed by a commercial 16-bit μP system

  6. Analysis of event-mode data with Interactive Data Language

    International Nuclear Information System (INIS)

    De Young, P.A.; Hilldore, B.B.; Kiessel, L.M.; Peaslee, G.F.

    2003-01-01

    We have developed an analysis package for event-mode data based on Interactive Data Language (IDL) from Research Systems Inc. This high-level language is high speed, array oriented, object oriented, and has extensive visual (multi-dimensional plotting) and mathematical functions. We have developed a general framework, written in IDL, for the analysis of a variety of experimental data that does not require significant customization for each analysis. Unlike many traditional analysis package, spectra and gates are applied after data are read and are easily changed as analysis proceeds without rereading the data. The events are not sequentially processed into predetermined arrays subject to predetermined gates

  7. Features of an advanced human reliability analysis method, AGAPE-ET

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Whan; Jung, Won Dea; Park, Jin Kyun [Korea Atomic Energy Research Institute, Taejeon (Korea, Republic of)

    2005-11-15

    This paper presents the main features of an advanced human reliability analysis (HRA) method, AGAPE-ET. It has the capabilities to deal with the diagnosis failures and the errors of commission (EOC), which have not been normally treated in the conventional HRAs. For the analysis of the potential for diagnosis failures, an analysis framework, which is called the misdiagnosis tree analysis (MDTA), and a taxonomy of the misdiagnosis causes with appropriate quantification schemes are provided. For the identification of the EOC events from the misdiagnosis, some procedural guidance is given. An example of the application of the method is also provided.

  8. Features of an advanced human reliability analysis method, AGAPE-ET

    International Nuclear Information System (INIS)

    Kim, Jae Whan; Jung, Won Dea; Park, Jin Kyun

    2005-01-01

    This paper presents the main features of an advanced human reliability analysis (HRA) method, AGAPE-ET. It has the capabilities to deal with the diagnosis failures and the errors of commission (EOC), which have not been normally treated in the conventional HRAs. For the analysis of the potential for diagnosis failures, an analysis framework, which is called the misdiagnosis tree analysis (MDTA), and a taxonomy of the misdiagnosis causes with appropriate quantification schemes are provided. For the identification of the EOC events from the misdiagnosis, some procedural guidance is given. An example of the application of the method is also provided

  9. Human reliability analysis for In-Tank Precipitation alignment and startup of emergency purge ventilation equipment

    International Nuclear Information System (INIS)

    Olsen, L.M.

    1993-08-01

    This report documents the methodology used for calculating the human error probability for establishing air based ventilation using emergency purge ventilation equipment on In-Tank Precipitation (ITP) processing tanks 48 and 49 after a failure of the nitrogen purge system following a seismic event. The analyses were performed according to THERP (Technique for Human Error Rate Prediction). The calculated human error probabilities are provided as input to the Fault Tree Analysis for the ITP Nitrogen Purge System. The analysis assumes a seismic event initiator leading to establishing air based ventilation on the ITP processing tanks 48 and 49. At the time of this analysis only the tanks and the emergency purge ventilation equipment are seismically qualified. Consequently, onsite and offsite power is assumed to be unavailable and all operator control actions are to be performed locally on the tank top. Assumptions regarding procedures, staffing, equipment locations, equipment tagging, equipment availability, and training were made and are documented in this report. The human error probability for establishing air based ventilation using the emergency purge ventilation equipment on In-Tank Precipitation processing tanks 48 and 49 after a failure of the nitrogen purge system following a seismic event is 4.2E-6 (median value on the lognormal scale). It is important to note that this result is predicated on the implementation of all of the assumptions listed in the ''Assumptions'' section of this report. This analysis was not based on the current conditions in ITP. The analysis is to be used as a tool to aid ITP operations personnel in achieving the training, procedural, and operational goals outlined in this document

  10. Attack Graph Construction for Security Events Analysis

    Directory of Open Access Journals (Sweden)

    Andrey Alexeevich Chechulin

    2014-09-01

    Full Text Available The paper is devoted to investigation of the attack graphs construction and analysis task for a network security evaluation and real-time security event processing. Main object of this research is the attack modeling process. The paper contains the description of attack graphs building, modifying and analysis technique as well as overview of implemented prototype for network security analysis based on attack graph approach.

  11. ORIONR: A simple and effective method for systemic analysis of clinical events and precursors occurring in hospital practice

    International Nuclear Information System (INIS)

    Debouck, F.; Petit, H.; Ravinet, L.; Rieger, E.; Noel, G.

    2012-01-01

    Purpose. - Morbi-mortality review is now recommended by the French Health Authority (Haute Autorite de sante [HAS]) in all hospital settings. It could be completed by Comites de retour d'experience (CREX), making systemic analysis of event precursors which may potentially result in medical damage. As commonly captured by their current practice, medical teams may not favour systemic analysis of events occurring in their setting. They require an easy-to-use method, more or less intuitive and easy-to-learn. It is the reason why ORION R has been set up. Methods. - ORION R is based on experience acquired in aeronautics which is the main precursor in risk management since aircraft crashes are considered as unacceptable even though the mortality from aircraft crashes is extremely low compared to the mortality from medical errors in hospital settings. The systemic analysis is divided in six steps: (i) collecting data, (ii) rebuilding the chronology of facts, (iii) identifying the gaps, (iv) identifying contributing and influential factors, (v) proposing actions to put in place, (vi) writing the analysis report. When identifying contributing and influential factors, four kinds of factors favouring the event are considered: technical domain, working environment, organisation and procedures, human factors. Although they are essentials, human factors are not always considered correctly. The systemic analysis is done by a pilot, chosen among people trained to use the method, querying information from all categories of people acting in the setting. Results. - ORION R is now used in more than 400 French hospital settings for systemic analysis of either morbi-mortality cases or event precursors. It is used, in particular, in 145 radiotherapy centres for supporting CREX. Conclusion. - As very simple to use and quasi-intuitive, ORION R is an asset to reach the objectives defined by HAS: to set up effective morbi-mortality reviews (RMM) and CREX for improving the quality of care in

  12. Application and Use of PSA-based Event Analysis in Belgium

    International Nuclear Information System (INIS)

    Hulsmans, M.; De Gelder, P.

    2003-01-01

    The paper describes the experiences of the Belgian nuclear regulatory body AVN with the application and the use of the PSAEA guidelines (PSA-based Event Analysis). In 2000, risk-based precursor analysis has increasingly become a part of the AVN process of feedback of operating experience, and constitutes in fact the first PSA application for the Belgian plants. The PSAEA guidelines were established by a consultant in the framework of an international project. In a first stage, AVN applied the PSAEA guidelines to two test cases in order to explore the feasibility and the interest of this type of probabilistic precursor analysis. These pilot studies demonstrated the applicability of the PSAEA method in general, and its applicability to the computer models of the Belgian state-of-the- art PSAs in particular. They revealed insights regarding the event analysis methodology, the resulting event severity and the PSA model itself. The consideration of relevant what-if questions allowed to identify - and in some cases also to quantify - several potential safety issues for improvement. The internal evaluation of PSAEA was positive and AVN decided to routinely perform several PSAEA studies per year. During 2000, PSAEA has increasingly become a part of the AVN process of feedback of operating experience. The objectives of the AVN precursor program have been clearly stated. A first pragmatic set of screening rules for operational events has been drawn up and applied. Six more operational events have been analysed in detail (initiating events as well as condition events) and resulted in a wide spectrum of event severity. In addition to the particular conclusions for each event, relevant insights have been gained regarding for instance event modelling and the interpretation of results. Particular attention has been devoted to the form of the analysis report. After an initial presentation of some key concepts, the particular context of this program and of AVN's objectives, the

  13. HiggsToFourLeptonsEV in the ATLAS EventView Analysis Framework

    CERN Document Server

    Lagouri, T; Del Peso, J

    2008-01-01

    ATLAS is one of the four experiments at the Large Hadron Collider (LHC) at CERN. This experiment has been designed to study a large range of physics topics, including searches for previously unobserved phenomena such as the Higgs Boson and super-symmetry. The physics analysis package HiggsToFourLeptonsEV for the Standard Model (SM) Higgs to four leptons channel with ATLAS is presented. The physics goal is to investigate with the ATLAS detector, the SM Higgs boson discovery potential through its observation in the four-lepton (electron and muon) final state. HiggsToFourLeptonsEV is based on the official ATLAS software ATHENA and the EventView (EV) analysis framework. EventView is a highly flexible and modular analysis framework in ATHENA and it is one of several analysis schemes for ATLAS physics user analysis. At the core of the EventView is the representative "view" of an event, which defines the contents of event data suitable for event-level physics analysis. The HiggsToFourLeptonsEV package, presented in ...

  14. Contrasting safety assessments of a runway incursion scenario: Event sequence analysis versus multi-agent dynamic risk modelling

    International Nuclear Information System (INIS)

    Stroeve, Sybert H.; Blom, Henk A.P.; Bakker, G.J.

    2013-01-01

    In the safety literature it has been argued, that in a complex socio-technical system safety cannot be well analysed by event sequence based approaches, but requires to capture the complex interactions and performance variability of the socio-technical system. In order to evaluate the quantitative and practical consequences of these arguments, this study compares two approaches to assess accident risk of an example safety critical sociotechnical system. It contrasts an event sequence based assessment with a multi-agent dynamic risk model (MA-DRM) based assessment, both of which are performed for a particular runway incursion scenario. The event sequence analysis uses the well-known event tree modelling formalism and the MA-DRM based approach combines agent based modelling, hybrid Petri nets and rare event Monte Carlo simulation. The comparison addresses qualitative and quantitative differences in the methods, attained risk levels, and in the prime factors influencing the safety of the operation. The assessments show considerable differences in the accident risk implications of the performance of human operators and technical systems in the runway incursion scenario. In contrast with the event sequence based results, the MA-DRM based results show that the accident risk is not manifest from the performance of and relations between individual human operators and technical systems. Instead, the safety risk emerges from the totality of the performance and interactions in the agent based model of the safety critical operation considered, which coincides very well with the argumentation in the safety literature.

  15. Physics analysis of the gang partial rod drive event

    International Nuclear Information System (INIS)

    Boman, C.; Frost, R.L.

    1992-08-01

    During the routine positioning of partial-length control rods in Gang 3 on the afternoon of Monday, July 27, 1992, the partial-length rods continued to drive into the reactor even after the operator released the controlling toggle switch. In response to this occurrence, the Safety Analysis and Engineering Services Group (SAEG) requested that the Applied Physics Group (APG) analyze the gang partial rod drive event. Although similar accident scenarios were considered in analysis for Chapter 15 of the Safety Analysis Report (SAR), APG and SAEG conferred and agreed that this particular type of gang partial-length rod motion event was not included in the SAR. This report details this analysis

  16. Multistate event history analysis with frailty

    Directory of Open Access Journals (Sweden)

    Govert Bijwaard

    2014-05-01

    Full Text Available Background: In survival analysis a large literature using frailty models, or models with unobserved heterogeneity, exists. In the growing literature and modelling on multistate models, this issue is only in its infant phase. Ignoring frailty can, however, produce incorrect results. Objective: This paper presents how frailties can be incorporated into multistate models, with an emphasis on semi-Markov multistate models with a mixed proportional hazard structure. Methods: First, the aspects of frailty modeling in univariate (proportional hazard, Cox and multivariate event history models are addressed. The implications of choosing shared or correlated frailty is highlighted. The relevant differences with recurrent events data are covered next. Multistate models are event history models that can have both multivariate and recurrent events. Incorporating frailty in multistate models, therefore, brings all the previously addressed issues together. Assuming a discrete frailty distribution allows for a very general correlation structure among the transition hazards in a multistate model. Although some estimation procedures are covered the emphasis is on conceptual issues. Results: The importance of multistate frailty modeling is illustrated with data on labour market and migration dynamics of recent immigrants to the Netherlands.

  17. Psychiatric adverse events during treatment with brodalumab: Analysis of psoriasis clinical trials.

    Science.gov (United States)

    Lebwohl, Mark G; Papp, Kim A; Marangell, Lauren B; Koo, John; Blauvelt, Andrew; Gooderham, Melinda; Wu, Jashin J; Rastogi, Shipra; Harris, Susan; Pillai, Radhakrishnan; Israel, Robert J

    2018-01-01

    Individuals with psoriasis are at increased risk for psychiatric comorbidities, including suicidal ideation and behavior (SIB). To distinguish between the underlying risk and potential for treatment-induced psychiatric adverse events in patients with psoriasis being treated with brodalumab, a fully human anti-interleukin 17 receptor A monoclonal antibody. Data were evaluated from a placebo-controlled, phase 2 clinical trial; the open-label, long-term extension of the phase 2 clinical trial; and three phase 3, randomized, double-blind, controlled clinical trials (AMAGINE-1, AMAGINE-2, and AMAGINE-3) and their open-label, long-term extensions of patients with moderate-to-severe psoriasis. The analysis included 4464 patients with 9161.8 patient-years of brodalumab exposure. The follow-up time-adjusted incidence rates of SIB events were comparable between the brodalumab and ustekinumab groups throughout the 52-week controlled phases (0.20 vs 0.60 per 100 patient-years). In the brodalumab group, 4 completed suicides were reported, 1 of which was later adjudicated as indeterminate; all patients had underlying psychiatric disorders or stressors. There was no comparator arm past week 52. Controlled study periods were not powered to detect differences in rare events such as suicide. Comparison with controls and the timing of events do not indicate a causal relationship between SIB and brodalumab treatment. Copyright © 2017 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  18. Human reliability analysis

    International Nuclear Information System (INIS)

    Dougherty, E.M.; Fragola, J.R.

    1988-01-01

    The authors present a treatment of human reliability analysis incorporating an introduction to probabilistic risk assessment for nuclear power generating stations. They treat the subject according to the framework established for general systems theory. Draws upon reliability analysis, psychology, human factors engineering, and statistics, integrating elements of these fields within a systems framework. Provides a history of human reliability analysis, and includes examples of the application of the systems approach

  19. Analysis of Employee's Survey for Preventing Human-Errors

    Energy Technology Data Exchange (ETDEWEB)

    Sung, Chanho; Kim, Younggab; Joung, Sanghoun [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    Human errors in nuclear power plant can cause large and small events or incidents. These events or incidents are one of main contributors of reactor trip and might threaten the safety of nuclear plants. To prevent human-errors, KHNP(nuclear power plants) introduced 'Human-error prevention techniques' and have applied the techniques to main parts such as plant operation, operation support, and maintenance and engineering. This paper proposes the methods to prevent and reduce human-errors in nuclear power plants through analyzing survey results which includes the utilization of the human-error prevention techniques and the employees' awareness of preventing human-errors. With regard to human-error prevention, this survey analysis presented the status of the human-error prevention techniques and the employees' awareness of preventing human-errors. Employees' understanding and utilization of the techniques was generally high and training level of employee and training effect on actual works were in good condition. Also, employees answered that the root causes of human-error were due to working environment including tight process, manpower shortage, and excessive mission rather than personal negligence or lack of personal knowledge. Consideration of working environment is certainly needed. At the present time, based on analyzing this survey, the best methods of preventing human-error are personal equipment, training/education substantiality, private mental health check before starting work, prohibit of multiple task performing, compliance with procedures, and enhancement of job site review. However, the most important and basic things for preventing human-error are interests of workers and organizational atmosphere such as communication between managers and workers, and communication between employees and bosses.

  20. Human kinematics and event control: On-line movement registration as a means for experimental manipulation

    NARCIS (Netherlands)

    Oudejans, R.R.D.; Coolen, H.

    2003-01-01

    In human movement and sports science, manipulations of perception and action are common and often comprise the control of events, such as opening or closing liquid crystal goggles. Most of these events are externally controlled, independent of the actions of the participants. Less common, although

  1. Genome-wide comparative analysis reveals human-mouse regulatory landscape and evolution.

    Science.gov (United States)

    Denas, Olgert; Sandstrom, Richard; Cheng, Yong; Beal, Kathryn; Herrero, Javier; Hardison, Ross C; Taylor, James

    2015-02-14

    Because species-specific gene expression is driven by species-specific regulation, understanding the relationship between sequence and function of the regulatory regions in different species will help elucidate how differences among species arise. Despite active experimental and computational research, relationships among sequence, conservation, and function are still poorly understood. We compared transcription factor occupied segments (TFos) for 116 human and 35 mouse TFs in 546 human and 125 mouse cell types and tissues from the Human and the Mouse ENCODE projects. We based the map between human and mouse TFos on a one-to-one nucleotide cross-species mapper, bnMapper, that utilizes whole genome alignments (WGA). Our analysis shows that TFos are under evolutionary constraint, but a substantial portion (25.1% of mouse and 25.85% of human on average) of the TFos does not have a homologous sequence on the other species; this portion varies among cell types and TFs. Furthermore, 47.67% and 57.01% of the homologous TFos sequence shows binding activity on the other species for human and mouse respectively. However, 79.87% and 69.22% is repurposed such that it binds the same TF in different cells or different TFs in the same cells. Remarkably, within the set of repurposed TFos, the corresponding genome regions in the other species are preferred locations of novel TFos. These events suggest exaptation of some functional regulatory sequences into new function. Despite TFos repurposing, we did not find substantial changes in their predicted target genes, suggesting that CRMs buffer evolutionary events allowing little or no change in the TFos - target gene associations. Thus, the small portion of TFos with strictly conserved occupancy underestimates the degree of conservation of regulatory interactions. We mapped regulatory sequences from an extensive number of TFs and cell types between human and mouse using WGA. A comparative analysis of this correspondence unveiled the

  2. Human reliability analysis during PSA at Trillo NPP: main characteristics and analysis of diagnostic errors

    International Nuclear Information System (INIS)

    Barquin, M.A.; Gomez, F.

    1998-01-01

    The design difference between Trillo NPP and other Spanish nuclear power plants (basic Westinghouse and General Electric designs) were made clear in the Human Reliability Analysis of the Probabilistic Safety Analysis (PSA) for Trillo NPP. The object of this paper is to describe the most significant characteristics of the Human Reliability Analysis carried out in the PSA, with special emphasis on the possible diagnostic errors and their consequences, based on the characteristics in the Emergency Operations Manual for Trillo NPP. - In the case of human errors before the initiating event (type 1), the existence of four redundancies in most of the plant safety systems, means that the impact of this type or error on the final results of the PSA is insignificant. However, in the case common cause errors, especially in certain calibration errors, some actions are significant in the final equation for core damage - The number of human actions that the operator has to carry out during the accidents (type 3) modelled, is relatively small in comparison with this value in other PSAs. This is basically due to the high level of automation at Rillo NPP - The Plant Operations Manual cannot be strictly considered to be a symptoms-based procedure. The operation Group must select the chapter from the Operations Manual to be followed, after having diagnosed the perturbing event, using for this purpose and Emergency and Anomaly Decision Tree (M.O.3.0.1) based on the different indications, alarms and symptoms present in the plant after the perturbing event. For this reason, it was decided to analyse the possible diagnosis errors. In the bibliography on diagnosis and commission errors available at the present time, there is no precise methodology for the analysis of this type of error and its incorporation into PSAs. The method used in the PSA for Trillo y NPP to evaluate this type of interaction, is to develop a Diagnosis Error Table, the object of which is to identify the situations in

  3. Impacts of Extreme Events on Human Health. Chapter 4

    Science.gov (United States)

    Bell, Jesse E.; Herring, Stephanie C.; Jantarasami, Lesley; Adrianopoli, Carl; Benedict, Kaitlin; Conlon, Kathryn; Escobar, Vanessa; Hess, Jeremy; Luvall, Jeffrey; Garcia-Pando, Carlos Perez; hide

    2016-01-01

    Increased Exposure to Extreme Events Key Finding 1: Health impacts associated with climate-related changes in exposure to extreme events include death, injury, or illness; exacerbation of underlying medical conditions; and adverse effects on mental health[High Confidence]. Climate change will increase exposure risk in some regions of the United States due to projected increases in the frequency and/or intensity of drought, wildfires, and flooding related to extreme precipitation and hurricanes [Medium Confidence].Disruption of Essential Infrastructure Key Finding 2: Many types of extreme events related to climate change cause disruption of infrastructure, including power, water, transportation, and communication systems, that are essential to maintaining access to health care and emergency response services and safeguarding human health [High Confidence].Vulnerability to Coastal Flooding Key Finding 3: Coastal populations with greater vulnerability to health impacts from coastal flooding include persons with disabilities or other access and functional needs, certain populations of color, older adults, pregnant women and children, low-income populations, and some occupational groups [High Confidence].Climate change will increase exposure risk to coastal flooding due to increases in extreme precipitation and in hurricane intensity and rainfall rates, as well as sea level rise and the resulting increases in storm surge.

  4. Static Analysis for Event-Based XML Processing

    DEFF Research Database (Denmark)

    Møller, Anders

    2008-01-01

    Event-based processing of XML data - as exemplified by the popular SAX framework - is a powerful alternative to using W3C's DOM or similar tree-based APIs. The event-based approach is a streaming fashion with minimal memory consumption. This paper discusses challenges for creating program analyses...... for SAX applications. In particular, we consider the problem of statically guaranteeing the a given SAX program always produces only well-formed and valid XML output. We propose an analysis technique based on ecisting anglyses of Servlets, string operations, and XML graphs....

  5. Human Reliability Analysis for In-Tank Precipitation Alignment and Startup of Emergency Purge Ventilation Equipment. Revision 3

    International Nuclear Information System (INIS)

    Shapiro, B.J.; Britt, T.E.

    1994-10-01

    This report documents the methodology used for calculating the human error probability for establishing air based ventilation using emergency purge ventilation equipment on In-Tank Precipitation (ITP) processing tanks 48 and 49 after failure of the nitrogen purge system following a seismic event. The analyses were performed according to THERP (Technique for Human Error Rate Prediction) as described in NUREG/CR-1278-F, ''Handbook of Human Reliability Analysis with Emphasis on Nuclear Power Plant Applications.'' The calculated human error probabilities are provided as input to the Fault Tree Analysis for the ITP Nitrogen Purge System

  6. Qualitative and quantitative methods for human factor analysis and assessment in NPP. Investigations and results

    International Nuclear Information System (INIS)

    Hristova, R.; Kalchev, B.; Atanasov, D.

    2005-01-01

    We consider here two basic groups of methods for analysis and assessment of the human factor in the NPP area and give some results from performed analyses as well. The human factor is the human interaction with the design equipment, with the working environment and takes into account the human capabilities and limits. In the frame of the qualitative methods for analysis of the human factor are considered concepts and structural methods for classifying of the information, connected with the human factor. Emphasize is given to the HPES method for human factor analysis in NPP. Methods for quantitative assessment of the human reliability are considered. These methods allow assigning of probabilities to the elements of the already structured information about human performance. This part includes overview of classical methods for human reliability assessment (HRA, THERP), and methods taking into account specific information about human capabilities and limits and about the man-machine interface (CHR, HEART, ATHEANA). Quantitative and qualitative results concerning human factor influence in the initiating events occurrences in the Kozloduy NPP are presented. (authors)

  7. A Dynamic Approach to Modeling Dependence Between Human Failure Events

    Energy Technology Data Exchange (ETDEWEB)

    Boring, Ronald Laurids [Idaho National Laboratory

    2015-09-01

    In practice, most HRA methods use direct dependence from THERP—the notion that error be- gets error, and one human failure event (HFE) may increase the likelihood of subsequent HFEs. In this paper, we approach dependence from a simulation perspective in which the effects of human errors are dynamically modeled. There are three key concepts that play into this modeling: (1) Errors are driven by performance shaping factors (PSFs). In this context, the error propagation is not a result of the presence of an HFE yielding overall increases in subsequent HFEs. Rather, it is shared PSFs that cause dependence. (2) PSFs have qualities of lag and latency. These two qualities are not currently considered in HRA methods that use PSFs. Yet, to model the effects of PSFs, it is not simply a matter of identifying the discrete effects of a particular PSF on performance. The effects of PSFs must be considered temporally, as the PSFs will have a range of effects across the event sequence. (3) Finally, there is the concept of error spilling. When PSFs are activated, they not only have temporal effects but also lateral effects on other PSFs, leading to emergent errors. This paper presents the framework for tying together these dynamic dependence concepts.

  8. Individual Differences in Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jeffrey C. Joe; Ronald L. Boring

    2014-06-01

    While human reliability analysis (HRA) methods include uncertainty in quantification, the nominal model of human error in HRA typically assumes that operator performance does not vary significantly when they are given the same initiating event, indicators, procedures, and training, and that any differences in operator performance are simply aleatory (i.e., random). While this assumption generally holds true when performing routine actions, variability in operator response has been observed in multiple studies, especially in complex situations that go beyond training and procedures. As such, complexity can lead to differences in operator performance (e.g., operator understanding and decision-making). Furthermore, psychological research has shown that there are a number of known antecedents (i.e., attributable causes) that consistently contribute to observable and systematically measurable (i.e., not random) differences in behavior. This paper reviews examples of individual differences taken from operational experience and the psychological literature. The impact of these differences in human behavior and their implications for HRA are then discussed. We propose that individual differences should not be treated as aleatory, but rather as epistemic. Ultimately, by understanding the sources of individual differences, it is possible to remove some epistemic uncertainty from analyses.

  9. Event Shape Analysis in ALICE

    CERN Document Server

    AUTHOR|(CDS)2073367; Paic, Guy

    2009-01-01

    The jets are the final state manifestation of the hard parton scattering. Since at LHC energies the production of hard processes in proton-proton collisions will be copious and varied, it is important to develop methods to identify them through the study of their final states. In the present work we describe a method based on the use of some shape variables to discriminate events according their topologies. A very attractive feature of this analysis is the possibility of using the tracking information of the TPC+ITS in order to identify specific events like jets. Through the correlation between the quantities: thrust and recoil, calculated in minimum bias simulations of proton-proton collisions at 10 TeV, we show the sensitivity of the method to select specific topologies and high multiplicity. The presented results were obtained both at level generator and after reconstruction. It remains that with any kind of jet reconstruction algorithm one will confronted in general with overlapping jets. The present meth...

  10. How to Cope with the Rare Human Error Events Involved with organizational Factors in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sa Kil; Luo, Meiling; Lee, Yong Hee [Korea Atomic Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    The current human error guidelines (e.g. US DOD handbooks, US NRC Guidelines) are representative tools to prevent human errors. These tools, however, have limits that they do not adapt all operating situations and circumstances such as design base events. In other words, these tools are only adapted foreseeable standardized operating situations and circumstances. In this study, our research team proposed an evidence-based approach such as UK's safety case to coping with the rare human error events such as TMI, Chernobyl, Fukushima accidents. These accidents are representative events involved with rare human errors. Our research team defined the 'rare human errors' as the follow three characterized events; Extremely low frequency Extremely high complicated structure Extremely serious damage of human life and property A safety case is a structured argument, supported by evidence, intended to justify that a system is acceptably safe. The definition by UK defense standard 00-56 issue 4 states that such an evidence-based approach can be contrast with a prescriptive approach to safety certification, which require safety to be justified using a prescribed process. Safety managements and safety regulatory activities based on safety case are effective to control organizational factors in terms of integrated safety management. Especially safety issues relevant with public acceptance are useful to provide practical evidences to the public reasonably. European Union including UK has developed the concept of engineered safety management system to deal with public acceptance using the safety case. In Korea nuclear industry, the Korean Atomic Research Institute has firstly performed a basic research to adapt the safety case in the field of radioactive waste according to the IAEA SSG-23(KAERI/TR-4497, 4531). Excepting the radioactive waste, there is no try to adapt the safety case yet. Most incidents and accidents involved human during operating NPPs have a tendency

  11. How to Cope with the Rare Human Error Events Involved with organizational Factors in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kim, Sa Kil; Luo, Meiling; Lee, Yong Hee

    2014-01-01

    The current human error guidelines (e.g. US DOD handbooks, US NRC Guidelines) are representative tools to prevent human errors. These tools, however, have limits that they do not adapt all operating situations and circumstances such as design base events. In other words, these tools are only adapted foreseeable standardized operating situations and circumstances. In this study, our research team proposed an evidence-based approach such as UK's safety case to coping with the rare human error events such as TMI, Chernobyl, Fukushima accidents. These accidents are representative events involved with rare human errors. Our research team defined the 'rare human errors' as the follow three characterized events; Extremely low frequency Extremely high complicated structure Extremely serious damage of human life and property A safety case is a structured argument, supported by evidence, intended to justify that a system is acceptably safe. The definition by UK defense standard 00-56 issue 4 states that such an evidence-based approach can be contrast with a prescriptive approach to safety certification, which require safety to be justified using a prescribed process. Safety managements and safety regulatory activities based on safety case are effective to control organizational factors in terms of integrated safety management. Especially safety issues relevant with public acceptance are useful to provide practical evidences to the public reasonably. European Union including UK has developed the concept of engineered safety management system to deal with public acceptance using the safety case. In Korea nuclear industry, the Korean Atomic Research Institute has firstly performed a basic research to adapt the safety case in the field of radioactive waste according to the IAEA SSG-23(KAERI/TR-4497, 4531). Excepting the radioactive waste, there is no try to adapt the safety case yet. Most incidents and accidents involved human during operating NPPs have a tendency

  12. Ontology-Based Vaccine Adverse Event Representation and Analysis.

    Science.gov (United States)

    Xie, Jiangan; He, Yongqun

    2017-01-01

    Vaccine is the one of the greatest inventions of modern medicine that has contributed most to the relief of human misery and the exciting increase in life expectancy. In 1796, an English country physician, Edward Jenner, discovered that inoculating mankind with cowpox can protect them from smallpox (Riedel S, Edward Jenner and the history of smallpox and vaccination. Proceedings (Baylor University. Medical Center) 18(1):21, 2005). Based on the vaccination worldwide, we finally succeeded in the eradication of smallpox in 1977 (Henderson, Vaccine 29:D7-D9, 2011). Other disabling and lethal diseases, like poliomyelitis and measles, are targeted for eradication (Bonanni, Vaccine 17:S120-S125, 1999).Although vaccine development and administration are tremendously successful and cost-effective practices to human health, no vaccine is 100% safe for everyone because each person reacts to vaccinations differently given different genetic background and health conditions. Although all licensed vaccines are generally safe for the majority of people, vaccinees may still suffer adverse events (AEs) in reaction to various vaccines, some of which can be serious or even fatal (Haber et al., Drug Saf 32(4):309-323, 2009). Hence, the double-edged sword of vaccination remains a concern.To support integrative AE data collection and analysis, it is critical to adopt an AE normalization strategy. In the past decades, different controlled terminologies, including the Medical Dictionary for Regulatory Activities (MedDRA) (Brown EG, Wood L, Wood S, et al., Drug Saf 20(2):109-117, 1999), the Common Terminology Criteria for Adverse Events (CTCAE) (NCI, The Common Terminology Criteria for Adverse Events (CTCAE). Available from: http://evs.nci.nih.gov/ftp1/CTCAE/About.html . Access on 7 Oct 2015), and the World Health Organization (WHO) Adverse Reactions Terminology (WHO-ART) (WHO, The WHO Adverse Reaction Terminology - WHO-ART. Available from: https://www.umc-products.com/graphics/28010.pdf

  13. Screening Analysis of Criticality Features, Events, and Processes for License Application

    International Nuclear Information System (INIS)

    J.A. McClure

    2004-01-01

    This report documents the screening analysis of postclosure criticality features, events, and processes. It addresses the probability of criticality events resulting from degradation processes as well as disruptive events (i.e., seismic, rock fall, and igneous). Probability evaluations are performed utilizing the configuration generator described in ''Configuration Generator Model'', a component of the methodology from ''Disposal Criticality Analysis Methodology Topical Report''. The total probability per package of criticality is compared against the regulatory probability criterion for inclusion of events established in 10 CFR 63.114(d) (consider only events that have at least one chance in 10,000 of occurring over 10,000 years). The total probability of criticality accounts for the evaluation of identified potential critical configurations of all baselined commercial and U.S. Department of Energy spent nuclear fuel waste form and waste package combinations, both internal and external to the waste packages. This criticality screening analysis utilizes available information for the 21-Pressurized Water Reactor Absorber Plate, 12-Pressurized Water Reactor Absorber Plate, 44-Boiling Water Reactor Absorber Plate, 24-Boiling Water Reactor Absorber Plate, and the 5-Defense High-Level Radioactive Waste/U.S. Department of Energy Short waste package types. Where defensible, assumptions have been made for the evaluation of the following waste package types in order to perform a complete criticality screening analysis: 21-Pressurized Water Reactor Control Rod, 5-Defense High-Level Radioactive Waste/U.S. Department of Energy Long, and 2-Multi-Canister Overpack/2-Defense High-Level Radioactive Waste package types. The inputs used to establish probabilities for this analysis report are based on information and data generated for the Total System Performance Assessment for the License Application, where available. This analysis report determines whether criticality is to be

  14. [ORION®: a simple and effective method for systemic analysis of clinical events and precursors occurring in hospital practice].

    Science.gov (United States)

    Debouck, F; Rieger, E; Petit, H; Noël, G; Ravinet, L

    2012-05-01

    Morbimortality review is now recommended by the French Health Authority (Haute Autorité de santé [HAS]) in all hospital settings. It could be completed by Comités de retour d'expérience (CREX), making systemic analysis of event precursors which may potentially result in medical damage. As commonly captured by their current practice, medical teams may not favour systemic analysis of events occurring in their setting. They require an easy-to-use method, more or less intuitive and easy-to-learn. It is the reason why ORION(®) has been set up. ORION(®) is based on experience acquired in aeronautics which is the main precursor in risk management since aircraft crashes are considered as unacceptable even though the mortality from aircraft crashes is extremely low compared to the mortality from medical errors in hospital settings. The systemic analysis is divided in six steps: (i) collecting data, (ii) rebuilding the chronology of facts, (iii) identifying the gaps, (iv) identifying contributing and influential factors, (v) proposing actions to put in place, (vi) writing the analysis report. When identifying contributing and influential factors, four kinds of factors favouring the event are considered: technical domain, working environment, organisation and procedures, human factors. Although they are essentials, human factors are not always considered correctly. The systemic analysis is done by a pilot, chosen among people trained to use the method, querying information from all categories of people acting in the setting. ORION(®) is now used in more than 400 French hospital settings for systemic analysis of either morbimortality cases or event precursors. It is used, in particular, in 145 radiotherapy centres for supporting CREX. As very simple to use and quasi-intuitive, ORION(®) is an asset to reach the objectives defined by HAS: to set up effective morbi-mortality reviews (RMM) and CREX for improving the quality of care in hospital settings. By helping the

  15. A human error taxonomy and its application to an automatic method accident analysis

    International Nuclear Information System (INIS)

    Matthews, R.H.; Winter, P.W.

    1983-01-01

    Commentary is provided on the quantification aspects of human factors analysis in risk assessment. Methods for quantifying human error in a plant environment are discussed and their application to system quantification explored. Such a programme entails consideration of the data base and a taxonomy of factors contributing to human error. A multi-levelled approach to system quantification is proposed, each level being treated differently drawing on the advantages of different techniques within the fault/event tree framework. Management, as controller of organization, planning and procedure, is assigned a dominant role. (author)

  16. Preliminary Analysis of the Common Cause Failure Events for Domestic Nuclear Power Plants

    International Nuclear Information System (INIS)

    Kang, Daeil; Han, Sanghoon

    2007-01-01

    It is known that the common cause failure (CCF) events have a great effect on the safety and probabilistic safety assessment (PSA) results of nuclear power plants (NPPs). However, the domestic studies have been mainly focused on the analysis method and modeling of CCF events. Thus, the analysis of the CCF events for domestic NPPs were performed to establish a domestic database for the CCF events and to deliver them to the operation office of the international common cause failure data exchange (ICDE) project. This paper presents the analysis results of the CCF events for domestic nuclear power plants

  17. Analysis of system and of course of events

    International Nuclear Information System (INIS)

    Hoertner, H.; Kersting, E.J.; Puetter, B.M.

    1986-01-01

    The analysis of the system and of the course of events is used to determine the frequency of core melt-out accidents and to describe the safety-related boundary conditions of appropriate accidents. The lecture is concerned with the effect of system changes in the reference plant and the effect of triggering events not assessed in detail or not sufficiently assessed in detail in phase A of the German Risk Study on the frequency of core melt-out accidents, the minimum requirements for system functions for controlling triggering events, i.e. to prevent core melt-out accidents, the reliability data important for reliability investigations and frequency assessments. (orig./DG) [de

  18. ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE-EVENT SIMULATION

    Science.gov (United States)

    2016-03-24

    ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION...in the United States. AFIT-ENV-MS-16-M-166 ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION...UNLIMITED. AFIT-ENV-MS-16-M-166 ANALYSIS OF INPATIENT HOSPITAL STAFF MENTAL WORKLOAD BY MEANS OF DISCRETE -EVENT SIMULATION Erich W

  19. One health and cyanobacteria in freshwater systems: animal illnesses and deaths are sentinel events for human health risks.

    Science.gov (United States)

    Hilborn, Elizabeth D; Beasley, Val R

    2015-04-20

    Harmful cyanobacterial blooms have adversely impacted human and animal health for thousands of years. Recently, the health impacts of harmful cyanobacteria blooms are becoming more frequently detected and reported. However, reports of human and animal illnesses or deaths associated with harmful cyanobacteria blooms tend to be investigated and reported separately. Consequently, professionals working in human or in animal health do not always communicate findings related to these events with one another. Using the One Health concept of integration and collaboration among health disciplines, we systematically review the existing literature to discover where harmful cyanobacteria-associated animal illnesses and deaths have served as sentinel events to warn of potential human health risks. We find that illnesses or deaths among livestock, dogs and fish are all potentially useful as sentinel events for the presence of harmful cyanobacteria that may impact human health. We also describe ways to enhance the value of reports of cyanobacteria-associated illnesses and deaths in animals to protect human health. Efficient monitoring of environmental and animal health in a One Health collaborative framework can provide vital warnings of cyanobacteria-associated human health risks.

  20. Systematic analysis of dependent human errors from the maintenance history at finnish NPPs - A status report

    Energy Technology Data Exchange (ETDEWEB)

    Laakso, K. [VTT Industrial Systems (Finland)

    2002-12-01

    Operating experience has shown missed detection events, where faults have passed inspections and functional tests to operating periods after the maintenance activities during the outage. The causes of these failures have often been complex event sequences, involving human and organisational factors. Especially common cause and other dependent failures of safety systems may significantly contribute to the reactor core damage risk. The topic has been addressed in the Finnish studies of human common cause failures, where experiences on latent human errors have been searched and analysed in detail from the maintenance history. The review of the bulk of the analysis results of the Olkiluoto and Loviisa plant sites shows that the instrumentation and control and electrical equipment is more prone to human error caused failure events than the other maintenance and that plant modifications and also predetermined preventive maintenance are significant sources of common cause failures. Most errors stem from the refuelling and maintenance outage period at the both sites, and less than half of the dependent errors were identified during the same outage. The dependent human errors originating from modifications could be reduced by a more tailored specification and coverage of their start-up testing programs. Improvements could also be achieved by a more case specific planning of the installation inspection and functional testing of complicated maintenance works or work objects of higher plant safety and availability importance. A better use and analysis of condition monitoring information for maintenance steering could also help. The feedback from discussions of the analysis results with plant experts and professionals is still crucial in developing the final conclusions and recommendations that meet the specific development needs at the plants. (au)

  1. Analysis of catchments response to severe drought event for ...

    African Journals Online (AJOL)

    Nafiisah

    The run sum analysis method was a sound method which indicates in ... intensity and duration of stream flow depletion between nearby catchments. ... threshold level analysis method, and allows drought events to be described in more.

  2. Implementation and test of proposals to integrate human factors in reporting and causal analysis in nuclear power plants

    International Nuclear Information System (INIS)

    Wilpert; Maimer, H.; Miller, R.; Fahlbruch, B.; Leiber, I.; Szameitat, S.; Baggen, R.; Gans, A.; Becker, G.

    1998-01-01

    The research project 'Implementation and Test of Proposals to integrate Human Factors in Reporting and Causal Analysis in Nuclear Power Plants' ('Implementation and Test', SR 2039/8) is based on two antecedent projects: 'Reporting System' (SR 2039/1) and 'Causal Analysis' (SR 2039/2). The project 'Implementation and Test' conducted various tests and introductory programs in cooperation with different target groups concerning the event analysis methodology 'SOL - Safety through Organizational Learning': Regulators, consultant organizations, union/works councillors and utilities. Thus, SOL was concurrently optimized and [apted for the practice in the German nuclear power industry. SOL was also validated in a German nuclear power plant using a concrete event. Results of the 'Implementation and Test' project demonstrate that SOL is fit to conduct event analyses practicably and economically with appropriate comprehensiveness and depth. SOL facilitates the identification of relevant contributing factors of events. This report concludes with various concrete proposals for the further development of the Program of the Federal Ministry of Environment, Nature Protection and Reactor Safety (BMU) and the Federal Agency of R[iation Protection (BfS) concerning 'The Contribution of Humans to Safety of Nuclear Power Plants'. (orig.) [de

  3. Event history analysis and the cross-section

    DEFF Research Database (Denmark)

    Keiding, Niels

    2006-01-01

    Examples are given of problems in event history analysis, where several time origins (generating calendar time, age, disease duration, time on study, etc.) are considered simultaneously. The focus is on complex sampling patterns generated around a cross-section. A basic tool is the Lexis diagram....

  4. Multidisciplinary framework for human reliability analysis with an application to errors of commission and dependencies

    International Nuclear Information System (INIS)

    Barriere, M.T.; Luckas, W.J.; Wreathall, J.; Cooper, S.E.; Bley, D.C.; Ramey-Smith, A.

    1995-08-01

    Since the early 1970s, human reliability analysis (HRA) has been considered to be an integral part of probabilistic risk assessments (PRAs). Nuclear power plant (NPP) events, from Three Mile Island through the mid-1980s, showed the importance of human performance to NPP risk. Recent events demonstrate that human performance continues to be a dominant source of risk. In light of these observations, the current limitations of existing HRA approaches become apparent when the role of humans is examined explicitly in the context of real NPP events. The development of new or improved HRA methodologies to more realistically represent human performance is recognized by the Nuclear Regulatory Commission (NRC) as a necessary means to increase the utility of PRAS. To accomplish this objective, an Improved HRA Project, sponsored by the NRC's Office of Nuclear Regulatory Research (RES), was initiated in late February, 1992, at Brookhaven National Laboratory (BNL) to develop an improved method for HRA that more realistically assesses the human contribution to plant risk and can be fully integrated with PRA. This report describes the research efforts including the development of a multidisciplinary HRA framework, the characterization and representation of errors of commission, and an approach for addressing human dependencies. The implications of the research and necessary requirements for further development also are discussed

  5. Multidisciplinary framework for human reliability analysis with an application to errors of commission and dependencies

    Energy Technology Data Exchange (ETDEWEB)

    Barriere, M.T.; Luckas, W.J. [Brookhaven National Lab., Upton, NY (United States); Wreathall, J. [Wreathall (John) and Co., Dublin, OH (United States); Cooper, S.E. [Science Applications International Corp., Reston, VA (United States); Bley, D.C. [PLG, Inc., Newport Beach, CA (United States); Ramey-Smith, A. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Systems Technology

    1995-08-01

    Since the early 1970s, human reliability analysis (HRA) has been considered to be an integral part of probabilistic risk assessments (PRAs). Nuclear power plant (NPP) events, from Three Mile Island through the mid-1980s, showed the importance of human performance to NPP risk. Recent events demonstrate that human performance continues to be a dominant source of risk. In light of these observations, the current limitations of existing HRA approaches become apparent when the role of humans is examined explicitly in the context of real NPP events. The development of new or improved HRA methodologies to more realistically represent human performance is recognized by the Nuclear Regulatory Commission (NRC) as a necessary means to increase the utility of PRAS. To accomplish this objective, an Improved HRA Project, sponsored by the NRC`s Office of Nuclear Regulatory Research (RES), was initiated in late February, 1992, at Brookhaven National Laboratory (BNL) to develop an improved method for HRA that more realistically assesses the human contribution to plant risk and can be fully integrated with PRA. This report describes the research efforts including the development of a multidisciplinary HRA framework, the characterization and representation of errors of commission, and an approach for addressing human dependencies. The implications of the research and necessary requirements for further development also are discussed.

  6. Trial application of a technique for human error analysis (ATHEANA)

    International Nuclear Information System (INIS)

    Bley, D.C.; Cooper, S.E.; Parry, G.W.

    1996-01-01

    The new method for HRA, ATHEANA, has been developed based on a study of the operating history of serious accidents and an understanding of the reasons why people make errors. Previous publications associated with the project have dealt with the theoretical framework under which errors occur and the retrospective analysis of operational events. This is the first attempt to use ATHEANA in a prospective way, to select and evaluate human errors within the PSA context

  7. Extreme Weather Events and Climate Change Attribution

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Katherine [National Academy of Sciences, Washington, DC (United States)

    2016-03-31

    A report from the National Academies of Sciences, Engineering, and Medicine concludes it is now possible to estimate the influence of climate change on some types of extreme events. The science of extreme event attribution has advanced rapidly in recent years, giving new insight to the ways that human-caused climate change can influence the magnitude or frequency of some extreme weather events. This report examines the current state of science of extreme weather attribution, and identifies ways to move the science forward to improve attribution capabilities. Confidence is strongest in attributing types of extreme events that are influenced by climate change through a well-understood physical mechanism, such as, the more frequent heat waves that are closely connected to human-caused global temperature increases, the report finds. Confidence is lower for other types of events, such as hurricanes, whose relationship to climate change is more complex and less understood at present. For any extreme event, the results of attribution studies hinge on how questions about the event's causes are posed, and on the data, modeling approaches, and statistical tools chosen for the analysis.

  8. Solar Energetic Particles Events and Human Exploration: Measurements in a Space Habitat

    Science.gov (United States)

    Narici, L.; Berrilli, F.; Casolino, M.; Del Moro, D.; Forte, R.; Giovannelli, L.; Martucci, M.; Mergè, M.; Picozza, P.; Rizzo, A.; Scardigli, S.; Sparvoli, R.; Zeitlin, C.

    2016-12-01

    Solar activity is the source of Space Weather disturbances. Flares, CME and coronal holes modulate physical conditions of circumterrestrial and interplanetary space and ultimately the fluxes of high-energy ionized particles, i.e., solar energetic particle (SEP) and galactic cosmic ray (GCR) background. This ionizing radiation affects spacecrafts and biological systems, therefore it is an important issue for human exploration of space. During a deep space travel (for example the trip to Mars) radiation risk thresholds may well be exceeded by the crew, so mitigation countermeasures must be employed. Solar particle events (SPE) constitute high risks due to their impulsive high rate dose. Forecasting SPE appears to be needed and also specifically tailored to the human exploration needs. Understanding the parameters of the SPE that produce events leading to higher health risks for the astronauts in deep space is therefore a first priority issue. Measurements of SPE effects with active devices in LEO inside the ISS can produce important information for the specific SEP measured, relative to the specific detector location in the ISS (in a human habitat with a shield typical of manned space-crafts). Active detectors can select data from specific geo-magnetic regions along the orbits, allowing geo-magnetic selections that best mimic deep space radiation. We present results from data acquired in 2010 - 2012 by the detector system ALTEA inside the ISS (18 SPEs detected). We compare this data with data from the detector Pamela on a LEO satellite, with the RAD data during the Curiosity Journey to Mars, with GOES data and with several Solar physical parameters. While several features of the radiation modulation are easily understood by the effect of the geomagnetic field, as an example we report a proportionality of the flux in the ISS with the energetic proton flux measured by GOES, some features appear more difficult to interpret. The final goal of this work is to find the

  9. Use of PSA for the analysis of operational events in nuclear power plants

    International Nuclear Information System (INIS)

    Hulsmans, M.

    2006-01-01

    An operational event is a safety-relevant incident that occurred in an industrial installation like a nuclear power plant (NPP). The probabilistic approach to event analysis focuses on the potential consequences of an operational event. Within its scope of application, it provides a quantitative assessment of the risk significance of this event (and similar events): it calculates the risk increase induced by the event. Such analyses may result in a more objective and a more accurate event severity measure than those provided by commonly used qualitative methods. Probabilistic event analysis complements the traditional event analysis approaches that are oriented towards the understanding of the (root) causes of an event. In practice, risk-based precursor analysis consists of the mapping of an operational event on a risk model of the installation, such as a probabilistic safety analysis (PSA) model. Precursor analyses result in an objective risk ranking of safety-significant events, called accident precursors. An unexpectedly high (or low) risk increase value is in itself already an important finding. This assessment also yields a lot of information on the structure of the risk, since the underlying dominant factors can easily be determined. Relevant 'what if' studies on similar events and conditions can be identified and performed (which is generally not considered in conventional event analysis), with the potential to yield even broader findings. The findings of such a structured assessment can be used for other purposes than merely risk ranking. The operational experience feedback process can be improved by helping to identify design measures and operational practices in order to prevent re-occurrence or in order to mitigate future consequences, and even to evaluate their expected effectiveness, contributing to the validation and prioritization of corrective measures. Confirmed and re-occurring precursors with correlated characteristics may point out opportunities

  10. PRELIMINARY SELECTION OF MGR DESIGN BASIS EVENTS

    International Nuclear Information System (INIS)

    Kappes, J.A.

    1999-01-01

    The purpose of this analysis is to identify the preliminary design basis events (DBEs) for consideration in the design of the Monitored Geologic Repository (MGR). For external events and natural phenomena (e.g., earthquake), the objective is to identify those initiating events that the MGR will be designed to withstand. Design criteria will ensure that radiological release scenarios resulting from these initiating events are beyond design basis (i.e., have a scenario frequency less than once per million years). For internal (i.e., human-induced and random equipment failures) events, the objective is to identify credible event sequences that result in bounding radiological releases. These sequences will be used to establish the design basis criteria for MGR structures, systems, and components (SSCs) design basis criteria in order to prevent or mitigate radiological releases. The safety strategy presented in this analysis for preventing or mitigating DBEs is based on the preclosure safety strategy outlined in ''Strategy to Mitigate Preclosure Offsite Exposure'' (CRWMS M andO 1998f). DBE analysis is necessary to provide feedback and requirements to the design process, and also to demonstrate compliance with proposed 10 CFR 63 (Dyer 1999b) requirements. DBE analysis is also required to identify and classify the SSCs that are important to safety (ITS)

  11. External events analysis in PSA studies for Czech NPPs

    International Nuclear Information System (INIS)

    Holy, J.; Hustak, S.; Kolar, L.; Jaros, M.; Hladky, M.; Mlady, O.

    2014-01-01

    The purpose of the paper is to summarize current status of natural external hazards analysis in the PSA projects maintained in Czech Republic for both Czech NPPs - Dukovany and Temelin. The focus of the presentation is put upon the basic milestones in external event analysis effort - identification of external hazards important for Czech NPPs sites, screening out of the irrelevant hazards, modeling of plant response to the initiating events, including the basic activities regarding vulnerability and fragility analysis (supported with on-site analysis), quantification of accident sequences, interpretation of results and development of measures decreasing external events risk. The following external hazards are discussed in the paper, which have been addressed during several last years in PSA projects for Czech NPPs: 1)seismicity, 2)extremely low temperature 3)extremely high temperature 4)extreme wind 5)extreme precipitation (water, snow) 6)transport of dangerous substances (as an example of man-made hazard with some differences identified in comparison with natural hazards) 7)other hazards, which are not considered as very important for Czech NPPs, were screened out in the initial phase of the analysis, but are known as potential problem areas abroad. The paper is a result of coordinated effort with participation of experts and staff from engineering support organization UJV Rez, a.s. and NPPs located in Czech Republic - Dukovany and Temelin. (authors)

  12. Analysis of event tree with imprecise inputs by fuzzy set theory

    International Nuclear Information System (INIS)

    Ahn, Kwang Il; Chun, Moon Hyun

    1990-01-01

    Fuzzy set theory approach is proposed as a method to analyze event trees with imprecise or linguistic input variables such as 'likely' or 'improbable' instead of the numerical probability. In this paper, it is shown how the fuzzy set theory can be applied to the event tree analysis. The result of this study shows that the fuzzy set theory approach can be applied as an acceptable and effective tool for analysis of the event tree with fuzzy type of inputs. Comparisons of the fuzzy theory approach with the probabilistic approach of computing probabilities of final states of the event tree through subjective weighting factors and LHS technique show that the two approaches have common factors and give reasonable results

  13. Managing human performance

    International Nuclear Information System (INIS)

    Strucic, M.; Kavsek, D.

    2004-01-01

    Human performance remains a significant factor for management attention not only from a reactor safety perspective, but also from a financial one. Recent significant events analysis shows that human errors are still dominant causes and contributors to them. An analysis of significant events in nuclear industry occurred through 15-years period revealed that three of four significant events were triggered by human error, although the number of events have dropped by more than a factor of four. A number of human performance breakdowns occurred in the application of errorprevention techniques. These included a lack of pre-job briefs, inadequate turnover of tasks, ineffective use of peer checking, inadequate procedure adherence, and failure to apply a questioning attitude when unexpected changes were encountered in the task. Attempts by the industry to improve human performance have traditionally focused at the worker level. However, human error occurs within the context of the organization, which can either foster or resist human error. The greatest room for improvement lies not only in the continued improvement of front-line worker performance but more so in the identification and elimination of weaknesses in the organizational and managerial domains that contributes to worker performance at the job site. Based on mentioned analysis, other industrial sources and own operating experience, NPP Krsko is paying more attention to improve human performance among own as well as contractor workers. Through series of programs and activities, such as Reactivity Management Program, Safety Culture Program, Self-assessment Program, Corrective Action Program, Plant Performance Monitoring Program, developed in last few years, and through new procedures, written guides and publications, training and management efforts, number of human errors is going to be reduced. Involvement of higher levels of NPP Krsko organization in promotion and use of Human Performance techniques is

  14. Review of the human reliability analysis performed for Empire State Electric Energy Research Corporation

    International Nuclear Information System (INIS)

    Swart, D.; Banz, I.

    1985-01-01

    The Empire State Electric Energy Research Corporation (ESEERCO) commissioned Westinghouse to conduct a human reliability analysis to identify and quantify human error probabilities associated with operator actions for four specific events which may occur in light water reactors: loss of coolant accident, steam generator tube rupture, steam/feed line break, and stuck open pressurizer spray valve. Human Error Probabilities (HEPs) derived from Swain's Technique for Human Error Rate Prediction (THERP) were compared to data obtained from simulator exercises. A correlation was found between the HEPs derived from Swain and the results of the simulator data. The results of this study provide a unique insight into human factors analysis. The HEPs obtained from such probabilistic studies can be used to prioritize scenarios for operator training situations, and thus improve the correlation between simulator exercises and real control room experiences

  15. The 'dirty downside' of global sporting events: focus on human trafficking for sexual exploitation.

    Science.gov (United States)

    Finkel, R; Finkel, M L

    2015-01-01

    Human trafficking is as complex human rights and public health issue. The issue of human trafficking for sexual exploitation at large global sporting events has proven to be elusive given the clandestine nature of the industry. This piece examines the issue from a public health perspective. This is a literature review of the 'most comprehensive' studies published on the topic. A PubMed search was done using MeSH terms 'human traffickings' and 'sex trafficking' and 'human rights abuses'. Subheadings included 'statistics and numerical data', 'legislation and jurispudence', 'prevention and control', and 'therapy'. Only papers published in English were reviewed. The search showed that very few well-designed empirical studies have been conducted on the topic and only one pertinent systematic review was identified. Findings show a high prevalence of physical violence among those trafficked compared to non-trafficked women. Sexually transmitted infections and HIV AIDS are prevalent and preventive care is virtually non-existent. Quantifying human trafficking for sexual exploitation at large global sporting events has proven to be elusive given the clandestine nature of the industry. This is not to say that human trafficking for sex as well as forced sexual exploitation does not occur. It almost certainly exists, but to what extent is the big question. It is a hidden problem on a global scale in plain view with tremendous public health implications. Copyright © 2014 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  16. A Human Performance Analysis on Emergency Tasks of a Nuclear Power Plant

    International Nuclear Information System (INIS)

    Jung, Wondea; Park, Jinkyun; Kim, Jae W.

    2007-01-01

    Considering risk-informed activities that require the probabilistic safety assessment (PSA) quality to be as high as possible, an HRA should be performed by using a systematic method with realistic plant specific data to meet the requirements for risk-informed applications. In order to obtain more objective HRA results, data extracted from real experiences or simulators is essential. To support HRA activities and researches, we have developed a human performance database, OPERA (Operator Performance and Reliability Analysis). This paper introduces a study to analyze an operators' performance time, which is the most crucial input for estimating a human error probability of a post-initiating human failure event

  17. A methodology for collection and analysis of human error data based on a cognitive model: IDA

    International Nuclear Information System (INIS)

    Shen, S.-H.; Smidts, C.; Mosleh, A.

    1997-01-01

    This paper presents a model-based human error taxonomy and data collection. The underlying model, IDA (described in two companion papers), is a cognitive model of behavior developed for analysis of the actions of nuclear power plant operating crew during abnormal situations. The taxonomy is established with reference to three external reference points (i.e. plant status, procedures, and crew) and four reference points internal to the model (i.e. information collected, diagnosis, decision, action). The taxonomy helps the analyst: (1) recognize errors as such; (2) categorize the error in terms of generic characteristics such as 'error in selection of problem solving strategies' and (3) identify the root causes of the error. The data collection methodology is summarized in post event operator interview and analysis summary forms. The root cause analysis methodology is illustrated using a subset of an actual event. Statistics, which extract generic characteristics of error prone behaviors and error prone situations are presented. Finally, applications of the human error data collection are reviewed. A primary benefit of this methodology is to define better symptom-based and other auxiliary procedures with associated training to minimize or preclude certain human errors. It also helps in design of control rooms, and in assessment of human error probabilities in the probabilistic risk assessment framework. (orig.)

  18. Regression analysis of mixed recurrent-event and panel-count data.

    Science.gov (United States)

    Zhu, Liang; Tong, Xinwei; Sun, Jianguo; Chen, Manhua; Srivastava, Deo Kumar; Leisenring, Wendy; Robison, Leslie L

    2014-07-01

    In event history studies concerning recurrent events, two types of data have been extensively discussed. One is recurrent-event data (Cook and Lawless, 2007. The Analysis of Recurrent Event Data. New York: Springer), and the other is panel-count data (Zhao and others, 2010. Nonparametric inference based on panel-count data. Test 20: , 1-42). In the former case, all study subjects are monitored continuously; thus, complete information is available for the underlying recurrent-event processes of interest. In the latter case, study subjects are monitored periodically; thus, only incomplete information is available for the processes of interest. In reality, however, a third type of data could occur in which some study subjects are monitored continuously, but others are monitored periodically. When this occurs, we have mixed recurrent-event and panel-count data. This paper discusses regression analysis of such mixed data and presents two estimation procedures for the problem. One is a maximum likelihood estimation procedure, and the other is an estimating equation procedure. The asymptotic properties of both resulting estimators of regression parameters are established. Also, the methods are applied to a set of mixed recurrent-event and panel-count data that arose from a Childhood Cancer Survivor Study and motivated this investigation. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  19. Human Reliability Analysis for Small Modular Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Ronald L. Boring; David I. Gertman

    2012-06-01

    Because no human reliability analysis (HRA) method was specifically developed for small modular reactors (SMRs), the application of any current HRA method to SMRs represents tradeoffs. A first- generation HRA method like THERP provides clearly defined activity types, but these activity types do not map to the human-system interface or concept of operations confronting SMR operators. A second- generation HRA method like ATHEANA is flexible enough to be used for SMR applications, but there is currently insufficient guidance for the analyst, requiring considerably more first-of-a-kind analyses and extensive SMR expertise in order to complete a quality HRA. Although no current HRA method is optimized to SMRs, it is possible to use existing HRA methods to identify errors, incorporate them as human failure events in the probabilistic risk assessment (PRA), and quantify them. In this paper, we provided preliminary guidance to assist the human reliability analyst and reviewer in understanding how to apply current HRA methods to the domain of SMRs. While it is possible to perform a satisfactory HRA using existing HRA methods, ultimately it is desirable to formally incorporate SMR considerations into the methods. This may require the development of new HRA methods. More practicably, existing methods need to be adapted to incorporate SMRs. Such adaptations may take the form of guidance on the complex mapping between conventional light water reactors and small modular reactors. While many behaviors and activities are shared between current plants and SMRs, the methods must adapt if they are to perform a valid and accurate analysis of plant personnel performance in SMRs.

  20. Uncertainty analysis of one Main Circulation Pump trip event at the Ignalina NPP

    International Nuclear Information System (INIS)

    Vileiniskis, V.; Kaliatka, A.; Uspuras, E.

    2004-01-01

    One Main Circulation Pump (MCP) trip event is an anticipated transient with expected frequency of approximately one event per year. There were a few events when one MCP was inadvertently tripped. The throughput of the rest running pumps in the affected Main Circulation Circuit loop increased, however, the total coolant flow through the affected loop decreased. The main question arises whether this coolant flow rate is sufficient for adequate core cooling. This paper presents an investigation of one MCP trip event at the Ignalina NPP. According to international practice, the transient analysis should consist of deterministic analysis by employing best-estimate codes and uncertainty analysis. For that purpose, the plant's RELAP5 model and the GRS (Germany) System for Uncertainty and Sensitivity Analysis package (SUSA) were employed. Uncertainty analysis of flow energy loss in different parts of the Main Circulation Circuit, initial conditions and code-selected models was performed. Such analysis allows to estimate the influence of separate parameters on calculation results and to find the modelling parameters that have the largest impact on the event studied. On the basis of this analysis, recommendations for the further improvement of the model have been developed. (author)

  1. Summary of 1991--1992 misadministration event investigations

    Energy Technology Data Exchange (ETDEWEB)

    Ostrom, L.T.; Leahy, T.J.; Novack, S.D. [EG and G Idaho, Inc., Idaho Falls, ID (United States)

    1994-03-01

    Investigation team composed of representatives of the Idaho National Engineering Laboratory (INEL), the US Nuclear Regulatory Commission (NRC), and subcontracts investigated and analyzed seven misadministration events selected by the NRC concerning medical radioisotopes. Each team was led by an INEL member and depending on the nature of the event, included three or more team members with appropriate expertise in radiation oncology, medical physics, nuclear medicine technology, risk analysis, and human factors. The investigations focused on causes of the event, consequences, mitigating actions, and corrective actions. The major findings are described in this report.

  2. Summary of 1991--1992 misadministration event investigations

    International Nuclear Information System (INIS)

    Ostrom, L.T.; Leahy, T.J.; Novack, S.D.

    1994-03-01

    Investigation team composed of representatives of the Idaho National Engineering Laboratory (INEL), the US Nuclear Regulatory Commission (NRC), and subcontracts investigated and analyzed seven misadministration events selected by the NRC concerning medical radioisotopes. Each team was led by an INEL member and depending on the nature of the event, included three or more team members with appropriate expertise in radiation oncology, medical physics, nuclear medicine technology, risk analysis, and human factors. The investigations focused on causes of the event, consequences, mitigating actions, and corrective actions. The major findings are described in this report

  3. OAE: The Ontology of Adverse Events.

    Science.gov (United States)

    He, Yongqun; Sarntivijai, Sirarat; Lin, Yu; Xiang, Zuoshuang; Guo, Abra; Zhang, Shelley; Jagannathan, Desikan; Toldo, Luca; Tao, Cui; Smith, Barry

    2014-01-01

    A medical intervention is a medical procedure or application intended to relieve or prevent illness or injury. Examples of medical interventions include vaccination and drug administration. After a medical intervention, adverse events (AEs) may occur which lie outside the intended consequences of the intervention. The representation and analysis of AEs are critical to the improvement of public health. The Ontology of Adverse Events (OAE), previously named Adverse Event Ontology (AEO), is a community-driven ontology developed to standardize and integrate data relating to AEs arising subsequent to medical interventions, as well as to support computer-assisted reasoning. OAE has over 3,000 terms with unique identifiers, including terms imported from existing ontologies and more than 1,800 OAE-specific terms. In OAE, the term 'adverse event' denotes a pathological bodily process in a patient that occurs after a medical intervention. Causal adverse events are defined by OAE as those events that are causal consequences of a medical intervention. OAE represents various adverse events based on patient anatomic regions and clinical outcomes, including symptoms, signs, and abnormal processes. OAE has been used in the analysis of several different sorts of vaccine and drug adverse event data. For example, using the data extracted from the Vaccine Adverse Event Reporting System (VAERS), OAE was used to analyse vaccine adverse events associated with the administrations of different types of influenza vaccines. OAE has also been used to represent and classify the vaccine adverse events cited in package inserts of FDA-licensed human vaccines in the USA. OAE is a biomedical ontology that logically defines and classifies various adverse events occurring after medical interventions. OAE has successfully been applied in several adverse event studies. The OAE ontological framework provides a platform for systematic representation and analysis of adverse events and of the factors (e

  4. Root Cause Analysis: Learning from Adverse Safety Events.

    Science.gov (United States)

    Brook, Olga R; Kruskal, Jonathan B; Eisenberg, Ronald L; Larson, David B

    2015-10-01

    Serious adverse events continue to occur in clinical practice, despite our best preventive efforts. It is essential that radiologists, both as individuals and as a part of organizations, learn from such events and make appropriate changes to decrease the likelihood that such events will recur. Root cause analysis (RCA) is a process to (a) identify factors that underlie variation in performance or that predispose an event toward undesired outcomes and (b) allow for development of effective strategies to decrease the likelihood of similar adverse events occurring in the future. An RCA process should be performed within the environment of a culture of safety, focusing on underlying system contributors and, in a confidential manner, taking into account the emotional effects on the staff involved. The Joint Commission now requires that a credible RCA be performed within 45 days for all sentinel or major adverse events, emphasizing the need for all radiologists to understand the processes with which an effective RCA can be performed. Several RCA-related tools that have been found to be useful in the radiology setting include the "five whys" approach to determine causation; cause-and-effect, or Ishikawa, diagrams; causal tree mapping; affinity diagrams; and Pareto charts. © RSNA, 2015.

  5. Special Experts Meeting: Identifying and Overcoming Barriers to the Effective Consideration of Human and Organizational Factors in Event Analysis and Root Cause Analysis. Nuclear Energy Agency / Working Group on Human and Organizational Factors

    International Nuclear Information System (INIS)

    2011-01-01

    The main mission of the Nuclear Energy Agency (NEA) Working Group on Human and Organisational Factors (WGHOF) is to improve the understanding and treatment of human and organisational factors (HOF) within the nuclear industry in order to support the continued safety performance of nuclear installations and improve the effectiveness of regulatory practices in member countries. WGHOF developed a CSNI (Committee on the Safety of Nuclear Installations) Activity Proposal Sheet (CAPS) outlining the work and milestones necessary towards achieving the following objectives: - Identify barriers to analyzing and correctly identifying the Human and Organisational Factors (HOF) causes of events; - Identify barriers to implementing lessons learned from these analyses; and - Develop recommendations for overcoming these barriers to: improve the identification of HOF causes of events and support the successful implementation of appropriate corrective actions The CAPS can be found in Appendix A. The first activity under the plan was the development of a questionnaire. This was distributed to WGHOF members and their counterparts from the Working Group on Operating Experience (WGOE). The questionnaire was comprised of 20 questions based on the objectives of the CSNI Activity Proposed Sheet. The intended survey participants were licensees with previous experience conducting root cause analyses. Responses were received from 26 respondents from 11 different countries. The results of the questionnaire were analyzed to identify themes for further discussion during a specialist meeting planned for September 2009. The following themes were presented during the WGHOF meeting in March of 2009 and endorsed for further work: - Roles and Influence of Senior Management, - Skills and Knowledge of the Investigators, - Qualitative Nature of HOF, - Influence of the Regulator, - Systematic Approach to Investigation. A summary of the questionnaire responses is provided in Appendix B

  6. Difference Image Analysis of Galactic Microlensing. II. Microlensing Events

    Energy Technology Data Exchange (ETDEWEB)

    Alcock, C.; Allsman, R. A.; Alves, D.; Axelrod, T. S.; Becker, A. C.; Bennett, D. P.; Cook, K. H.; Drake, A. J.; Freeman, K. C.; Griest, K. (and others)

    1999-09-01

    The MACHO collaboration has been carrying out difference image analysis (DIA) since 1996 with the aim of increasing the sensitivity to the detection of gravitational microlensing. This is a preliminary report on the application of DIA to galactic bulge images in one field. We show how the DIA technique significantly increases the number of detected lensing events, by removing the positional dependence of traditional photometry schemes and lowering the microlensing event detection threshold. This technique, unlike PSF photometry, gives the unblended colors and positions of the microlensing source stars. We present a set of criteria for selecting microlensing events from objects discovered with this technique. The 16 pixel and classical microlensing events discovered with the DIA technique are presented. (c) (c) 1999. The American Astronomical Society.

  7. Civil protection and Damaging Hydrogeological Events: comparative analysis of the 2000 and 2015 events in Calabria (southern Italy

    Directory of Open Access Journals (Sweden)

    O. Petrucci

    2017-11-01

    Full Text Available Calabria (southern Italy is a flood prone region, due to both its rough orography and fast hydrologic response of most watersheds. During the rainy season, intense rain affects the region, triggering floods and mass movements that cause economic damage and fatalities. This work presents a methodological approach to perform the comparative analysis of two events affecting the same area at a distance of 15 years, by collecting all the qualitative and quantitative features useful to describe both rain and damage. The aim is to understand if similar meteorological events affecting the same area can have different outcomes in terms of damage. The first event occurred between 8 and 10 September 2000, damaged 109 out of 409 municipalities of the region and killed 13 people in a campsite due to a flood. The second event, which occurred between 30 October and 1 November 2015, damaged 79 municipalities, and killed a man due to a flood. The comparative analysis highlights that, despite the exceptionality of triggering daily rain was higher in the 2015 event, the damage caused by the 2000 event to both infrastructures and belongings was higher, and it was strongly increased due to the 13 flood victims. We concluded that, in the 2015 event, the management of pre-event phases, with the issuing of meteorological alert, and the emergency management, with the preventive evacuation of people in hazardous situations due to landslides or floods, contributed to reduce the number of victims.

  8. Evaluation of the HadGEM3-A simulations in view of detection and attribution of human influence on extreme events in Europe

    Science.gov (United States)

    Vautard, Robert; Christidis, Nikolaos; Ciavarella, Andrew; Alvarez-Castro, Carmen; Bellprat, Omar; Christiansen, Bo; Colfescu, Ioana; Cowan, Tim; Doblas-Reyes, Francisco; Eden, Jonathan; Hauser, Mathias; Hegerl, Gabriele; Hempelmann, Nils; Klehmet, Katharina; Lott, Fraser; Nangini, Cathy; Orth, René; Radanovics, Sabine; Seneviratne, Sonia I.; van Oldenborgh, Geert Jan; Stott, Peter; Tett, Simon; Wilcox, Laura; Yiou, Pascal

    2018-04-01

    A detailed analysis is carried out to assess the HadGEM3-A global atmospheric model skill in simulating extreme temperatures, precipitation and storm surges in Europe in the view of their attribution to human influence. The analysis is performed based on an ensemble of 15 atmospheric simulations forced with observed sea surface temperature of the 54 year period 1960-2013. These simulations, together with dual simulations without human influence in the forcing, are intended to be used in weather and climate event attribution. The analysis investigates the main processes leading to extreme events, including atmospheric circulation patterns, their links with temperature extremes, land-atmosphere and troposphere-stratosphere interactions. It also compares observed and simulated variability, trends and generalized extreme value theory parameters for temperature and precipitation. One of the most striking findings is the ability of the model to capture North-Atlantic atmospheric weather regimes as obtained from a cluster analysis of sea level pressure fields. The model also reproduces the main observed weather patterns responsible for temperature and precipitation extreme events. However, biases are found in many physical processes. Slightly excessive drying may be the cause of an overestimated summer interannual variability and too intense heat waves, especially in central/northern Europe. However, this does not seem to hinder proper simulation of summer temperature trends. Cold extremes appear well simulated, as well as the underlying blocking frequency and stratosphere-troposphere interactions. Extreme precipitation amounts are overestimated and too variable. The atmospheric conditions leading to storm surges were also examined in the Baltics region. There, simulated weather conditions appear not to be leading to strong enough storm surges, but winds were found in very good agreement with reanalyses. The performance in reproducing atmospheric weather patterns

  9. Cause trending analysis for licensing operational events in Daya Bay Nuclear Power Station

    International Nuclear Information System (INIS)

    Wang Dewei

    2005-01-01

    The human causal factors for all human error licensing operational events on Daya Bay nuclear power station since 1993 to 2003 are categorized, the trend of these causal factors is analyzed. The emphasis is placed on analyzing the deficiencies on complying with and executing regulations and procedures. The results provide directional reference for nuclear power station to improve human performance. (author)

  10. Reducing the incidence of adverse events in anesthesia practice

    OpenAIRE

    BELAVIĆ, MATIJA; LONČARIĆ-KATUŠIN, MIRJANA; ŽUNIĆ, JOSIP

    2013-01-01

    Background and purpose: adverse event during anesthesia is defined as an event that may result in the development of complications and is caused by human error, failure of the apparatus, the selected anesthetic techniques and individual reaction of the patient. Timely detection of adverse events prevents complications and their analysis through the register of the same to the adoption of preventive and remedial measures. Materials and methods:The Department of Anesthesiology in General...

  11. Music-Elicited Emotion Identification Using Optical Flow Analysis of Human Face

    Science.gov (United States)

    Kniaz, V. V.; Smirnova, Z. N.

    2015-05-01

    Human emotion identification from image sequences is highly demanded nowadays. The range of possible applications can vary from an automatic smile shutter function of consumer grade digital cameras to Biofied Building technologies, which enables communication between building space and residents. The highly perceptual nature of human emotions leads to the complexity of their classification and identification. The main question arises from the subjective quality of emotional classification of events that elicit human emotions. A variety of methods for formal classification of emotions were developed in musical psychology. This work is focused on identification of human emotions evoked by musical pieces using human face tracking and optical flow analysis. Facial feature tracking algorithm used for facial feature speed and position estimation is presented. Facial features were extracted from each image sequence using human face tracking with local binary patterns (LBP) features. Accurate relative speeds of facial features were estimated using optical flow analysis. Obtained relative positions and speeds were used as the output facial emotion vector. The algorithm was tested using original software and recorded image sequences. The proposed technique proves to give a robust identification of human emotions elicited by musical pieces. The estimated models could be used for human emotion identification from image sequences in such fields as emotion based musical background or mood dependent radio.

  12. Initiating events in the safety probabilistic analysis of nuclear power plants

    International Nuclear Information System (INIS)

    Stasiulevicius, R.

    1989-01-01

    The importance of the initiating event in the probabilistic safety analysis of nuclear power plants are discussed and the basic procedures necessary for preparing reports, quantification and grouping of the events are described. The examples of initiating events with its occurence medium frequency, included those calculated for OCONEE reactor and Angra-1 reactor are presented. (E.G.)

  13. An overview of the evolution of human reliability analysis in the context of probabilistic risk assessment

    International Nuclear Information System (INIS)

    Bley, Dennis C.; Lois, Erasmia; Kolaczkowski, Alan M.; Forester, John Alan; Wreathall, John; Cooper, Susan E.

    2009-01-01

    Since the Reactor Safety Study in the early 1970's, human reliability analysis (HRA) has been evolving towards a better ability to account for the factors and conditions that can lead humans to take unsafe actions and thereby provide better estimates of the likelihood of human error for probabilistic risk assessments (PRAs). The purpose of this paper is to provide an overview of recent reviews of operational events and advances in the behavioral sciences that have impacted the evolution of HRA methods and contributed to improvements. The paper discusses the importance of human errors in complex human-technical systems, examines why humans contribute to accidents and unsafe conditions, and discusses how lessons learned over the years have changed the perspective and approach for modeling human behavior in PRAs of complicated domains such as nuclear power plants. It is argued that it has become increasingly more important to understand and model the more cognitive aspects of human performance and to address the broader range of factors that have been shown to influence human performance in complex domains. The paper concludes by addressing the current ability of HRA to adequately predict human failure events and their likelihood

  14. An overview of the evolution of human reliability analysis in the context of probabilistic risk assessment.

    Energy Technology Data Exchange (ETDEWEB)

    Bley, Dennis C. (Buttonwood Consulting Inc., Oakton, VA); Lois, Erasmia (U.S. Nuclear Regulatory Commission, Washington, DC); Kolaczkowski, Alan M. (Science Applications International Corporation, Eugene, OR); Forester, John Alan; Wreathall, John (John Wreathall and Co., Dublin, OH); Cooper, Susan E. (U.S. Nuclear Regulatory Commission, Washington, DC)

    2009-01-01

    Since the Reactor Safety Study in the early 1970's, human reliability analysis (HRA) has been evolving towards a better ability to account for the factors and conditions that can lead humans to take unsafe actions and thereby provide better estimates of the likelihood of human error for probabilistic risk assessments (PRAs). The purpose of this paper is to provide an overview of recent reviews of operational events and advances in the behavioral sciences that have impacted the evolution of HRA methods and contributed to improvements. The paper discusses the importance of human errors in complex human-technical systems, examines why humans contribute to accidents and unsafe conditions, and discusses how lessons learned over the years have changed the perspective and approach for modeling human behavior in PRAs of complicated domains such as nuclear power plants. It is argued that it has become increasingly more important to understand and model the more cognitive aspects of human performance and to address the broader range of factors that have been shown to influence human performance in complex domains. The paper concludes by addressing the current ability of HRA to adequately predict human failure events and their likelihood.

  15. An analysis of post-event processing in social anxiety disorder.

    Science.gov (United States)

    Brozovich, Faith; Heimberg, Richard G

    2008-07-01

    Research has demonstrated that self-focused thoughts and negative affect have a reciprocal relationship [Mor, N., Winquist, J. (2002). Self-focused attention and negative affect: A meta-analysis. Psychological Bulletin, 128, 638-662]. In the anxiety disorder literature, post-event processing has emerged as a specific construction of repetitive self-focused thoughts that pertain to social anxiety disorder. Post-event processing can be defined as an individual's repeated consideration and potential reconstruction of his performance following a social situation. Post-event processing can also occur when an individual anticipates a social or performance event and begins to brood about other, past social experiences. The present review examined the post-event processing literature in an attempt to organize and highlight the significant results. The methodologies employed to study post-event processing have included self-report measures, daily diaries, social or performance situations created in the laboratory, and experimental manipulations of post-event processing or anticipation of an upcoming event. Directions for future research on post-event processing are discussed.

  16. Integrating natural language processing expertise with patient safety event review committees to improve the analysis of medication events.

    Science.gov (United States)

    Fong, Allan; Harriott, Nicole; Walters, Donna M; Foley, Hanan; Morrissey, Richard; Ratwani, Raj R

    2017-08-01

    Many healthcare providers have implemented patient safety event reporting systems to better understand and improve patient safety. Reviewing and analyzing these reports is often time consuming and resource intensive because of both the quantity of reports and length of free-text descriptions in the reports. Natural language processing (NLP) experts collaborated with clinical experts on a patient safety committee to assist in the identification and analysis of medication related patient safety events. Different NLP algorithmic approaches were developed to identify four types of medication related patient safety events and the models were compared. Well performing NLP models were generated to categorize medication related events into pharmacy delivery delays, dispensing errors, Pyxis discrepancies, and prescriber errors with receiver operating characteristic areas under the curve of 0.96, 0.87, 0.96, and 0.81 respectively. We also found that modeling the brief without the resolution text generally improved model performance. These models were integrated into a dashboard visualization to support the patient safety committee review process. We demonstrate the capabilities of various NLP models and the use of two text inclusion strategies at categorizing medication related patient safety events. The NLP models and visualization could be used to improve the efficiency of patient safety event data review and analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Disruptive event analysis: volcanism and igneous intrusion

    International Nuclear Information System (INIS)

    Crowe, B.M.

    1979-01-01

    Three basic topics are addressed for the disruptive event analysis: first, the range of disruptive consequences of a radioactive waste repository by volcanic activity; second, the possible reduction of the risk of disruption by volcanic activity through selective siting of a repository; and third, the quantification of the probability of repository disruption by volcanic activity

  18. Technique for human-error sequence identification and signification

    International Nuclear Information System (INIS)

    Heslinga, G.

    1988-01-01

    The aim of the present study was to investigate whether the event-tree technique can be used for the analysis of sequences of human errors that could cause initiating events. The scope of the study was limited to a consideration of the performance of procedural actions. The event-tree technique was modified to adapt it for this study and will be referred to as the 'Technique for Human-Error-Sequence Identification and Signification' (THESIS). The event trees used in this manner, i.e. THESIS event trees, appear to present additional problems if they are applied to human performance instead of technical systems. These problems, referred to as the 'Man-Related Features' of THESIS, are: the human capability to choose among several procedures, the ergonomics of the panel layout, human actions of a continuous nature, dependence between human errors, human capability to recover possible errors, the influence of memory during the recovery attempt, variability in human performance and correlations between human;erropr probabilities. The influence of these problems on the applicability of THESIS was assessed by means of mathematical analysis, field studies and laboratory experiments (author). 130 refs.; 51 figs.; 24 tabs

  19. Quantifications and Modeling of Human Failure Events in a Fire PSA

    International Nuclear Information System (INIS)

    Kang, Dae Il; Kim, Kilyoo; Jang, Seung-Cheol

    2014-01-01

    USNRC and EPRI developed guidance, 'Fire Human Reliability Analysis Guidelines, NUREG-1921', for estimating human error probabilities (HEPs) for HFEs under fire conditions. NUREG-1921 classifies HFEs into four types associated with the following human actions: - Type 1: New and existing Main Control Room (MCR) actions - Type 2: New and existing ex-MCR actions - Type 3: Actions associated with using alternate shutdown means (ASD) - Type 4: Actions relating to the error of commissions (EOCs) or error of omissions (EOOs) as a result of incorrect indications (SPI) In this paper, approaches for the quantifications and modeling of HFEs related to Type 1, 2 and 3 human actions are introduced. This paper introduced the human reliability analysis process for a fire PSA of Hanul Unit 3. A multiplier of 10 was used to re-estimate the HEPs for the preexisting internal human actions. The HEPs for all ex- MCR actions were assumed to be one. New MCR human actions were quantified using the scoping analysis method of NUREG-1921. If the quantified human action were identified to be risk-significant, detailed approaches (modeling and quantification) were used for incorporating fire situations into them. Multiple HFEs for single human action were defined and they were separately and were separately quantified to incorporate the specific fire situations into them. From this study, we can confirm that the modeling as well as quantifications of human actions is very important to appropriately treat them in PSA logic structures

  20. Quantifications and Modeling of Human Failure Events in a Fire PSA

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Dae Il; Kim, Kilyoo; Jang, Seung-Cheol [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-10-15

    USNRC and EPRI developed guidance, 'Fire Human Reliability Analysis Guidelines, NUREG-1921', for estimating human error probabilities (HEPs) for HFEs under fire conditions. NUREG-1921 classifies HFEs into four types associated with the following human actions: - Type 1: New and existing Main Control Room (MCR) actions - Type 2: New and existing ex-MCR actions - Type 3: Actions associated with using alternate shutdown means (ASD) - Type 4: Actions relating to the error of commissions (EOCs) or error of omissions (EOOs) as a result of incorrect indications (SPI) In this paper, approaches for the quantifications and modeling of HFEs related to Type 1, 2 and 3 human actions are introduced. This paper introduced the human reliability analysis process for a fire PSA of Hanul Unit 3. A multiplier of 10 was used to re-estimate the HEPs for the preexisting internal human actions. The HEPs for all ex- MCR actions were assumed to be one. New MCR human actions were quantified using the scoping analysis method of NUREG-1921. If the quantified human action were identified to be risk-significant, detailed approaches (modeling and quantification) were used for incorporating fire situations into them. Multiple HFEs for single human action were defined and they were separately and were separately quantified to incorporate the specific fire situations into them. From this study, we can confirm that the modeling as well as quantifications of human actions is very important to appropriately treat them in PSA logic structures.

  1. Organization of pulse-height analysis programs for high event rates

    Energy Technology Data Exchange (ETDEWEB)

    Cohn, C E [Argonne National Lab., Ill. (USA)

    1976-09-01

    The ability of a pulse-height analysis program to handle high event rates can be enhanced by organizing it so as to minimize the time spent in interrupt housekeeping. Specifically, the routine that services the data-ready interrupt from the ADC should test whether another event is ready before performing the interrupt return.

  2. The application of two recently developed human reliability techniques to cognitive error analysis

    International Nuclear Information System (INIS)

    Gall, W.

    1990-01-01

    Cognitive error can lead to catastrophic consequences for manned systems, including those whose design renders them immune to the effects of physical slips made by operators. Four such events, pressurized water and boiling water reactor accidents which occurred recently, were analysed. The analysis identifies the factors which contributed to the errors and suggests practical strategies for error recovery or prevention. Two types of analysis were conducted: an unstructured analysis based on the analyst's knowledge of psychological theory, and a structured analysis using two recently-developed human reliability analysis techniques. In general, the structured techniques required less effort to produce results and these were comparable to those of the unstructured analysis. (author)

  3. External events analysis for the Savannah River Site K reactor

    International Nuclear Information System (INIS)

    Brandyberry, M.D.; Wingo, H.E.

    1990-01-01

    The probabilistic external events analysis performed for the Savannah River Site K-reactor PRA considered many different events which are generally perceived to be ''external'' to the reactor and its systems, such as fires, floods, seismic events, and transportation accidents (as well as many others). Events which have been shown to be significant contributors to risk include seismic events, tornados, a crane failure scenario, fires and dam failures. The total contribution to the core melt frequency from external initiators has been found to be 2.2 x 10 -4 per year, from which seismic events are the major contributor (1.2 x 10 -4 per year). Fire initiated events contribute 1.4 x 10 -7 per year, tornados 5.8 x 10 -7 per year, dam failures 1.5 x 10 -6 per year and the crane failure scenario less than 10 -4 per year to the core melt frequency. 8 refs., 3 figs., 5 tabs

  4. Analysis of arrhythmic events is useful to detect lead failure earlier in patients followed by remote monitoring.

    Science.gov (United States)

    Nishii, Nobuhiro; Miyoshi, Akihito; Kubo, Motoki; Miyamoto, Masakazu; Morimoto, Yoshimasa; Kawada, Satoshi; Nakagawa, Koji; Watanabe, Atsuyuki; Nakamura, Kazufumi; Morita, Hiroshi; Ito, Hiroshi

    2018-03-01

    Remote monitoring (RM) has been advocated as the new standard of care for patients with cardiovascular implantable electronic devices (CIEDs). RM has allowed the early detection of adverse clinical events, such as arrhythmia, lead failure, and battery depletion. However, lead failure was often identified only by arrhythmic events, but not impedance abnormalities. To compare the usefulness of arrhythmic events with conventional impedance abnormalities for identifying lead failure in CIED patients followed by RM. CIED patients in 12 hospitals have been followed by the RM center in Okayama University Hospital. All transmitted data have been analyzed and summarized. From April 2009 to March 2016, 1,873 patients have been followed by the RM center. During the mean follow-up period of 775 days, 42 lead failure events (atrial lead 22, right ventricular pacemaker lead 5, implantable cardioverter defibrillator [ICD] lead 15) were detected. The proportion of lead failures detected only by arrhythmic events, which were not detected by conventional impedance abnormalities, was significantly higher than that detected by impedance abnormalities (arrhythmic event 76.2%, 95% CI: 60.5-87.9%; impedance abnormalities 23.8%, 95% CI: 12.1-39.5%). Twenty-seven events (64.7%) were detected without any alert. Of 15 patients with ICD lead failure, none has experienced inappropriate therapy. RM can detect lead failure earlier, before clinical adverse events. However, CIEDs often diagnose lead failure as just arrhythmic events without any warning. Thus, to detect lead failure earlier, careful human analysis of arrhythmic events is useful. © 2017 Wiley Periodicals, Inc.

  5. Contingency Analysis of Cascading Line Outage Events

    Energy Technology Data Exchange (ETDEWEB)

    Thomas L Baldwin; Magdy S Tawfik; Miles McQueen

    2011-03-01

    As the US power systems continue to increase in size and complexity, including the growth of smart grids, larger blackouts due to cascading outages become more likely. Grid congestion is often associated with a cascading collapse leading to a major blackout. Such a collapse is characterized by a self-sustaining sequence of line outages followed by a topology breakup of the network. This paper addresses the implementation and testing of a process for N-k contingency analysis and sequential cascading outage simulation in order to identify potential cascading modes. A modeling approach described in this paper offers a unique capability to identify initiating events that may lead to cascading outages. It predicts the development of cascading events by identifying and visualizing potential cascading tiers. The proposed approach was implemented using a 328-bus simplified SERC power system network. The results of the study indicate that initiating events and possible cascading chains may be identified, ranked and visualized. This approach may be used to improve the reliability of a transmission grid and reduce its vulnerability to cascading outages.

  6. Discrete dynamic event tree modeling and analysis of nuclear power plant crews for safety assessment

    International Nuclear Information System (INIS)

    Mercurio, D.

    2011-01-01

    Current Probabilistic Risk Assessment (PRA) and Human Reliability Analysis (HRA) methodologies model the evolution of accident sequences in Nuclear Power Plants (NPPs) mainly based on Logic Trees. The evolution of these sequences is a result of the interactions between the crew and plant; in current PRA methodologies, simplified models of these complex interactions are used. In this study, the Accident Dynamic Simulator (ADS), a modeling framework based on the Discrete Dynamic Event Tree (DDET), has been used for the simulation of crew-plant interactions during potential accident scenarios in NPPs. In addition, an operator/crew model has been developed to treat the response of the crew to the plant. The 'crew model' is made up of three operators whose behavior is guided by a set of rules-of-behavior (which represents the knowledge and training of the operators) coupled with written and mental procedures. In addition, an approach for addressing the crew timing variability in DDETs has been developed and implemented based on a set of HRA data from a simulator study. Finally, grouping techniques were developed and applied to the analysis of the scenarios generated by the crew-plant simulation. These techniques support the post-simulation analysis by grouping similar accident sequences, identifying the key contributing events, and quantifying the conditional probability of the groups. These techniques are used to characterize the context of the crew actions in order to obtain insights for HRA. The model has been applied for the analysis of a Small Loss Of Coolant Accident (SLOCA) event for a Pressurized Water Reactor (PWR). The simulation results support an improved characterization of the performance conditions or context of operator actions, which can be used in an HRA, in the analysis of the reliability of the actions. By providing information on the evolution of system indications, dynamic of cues, crew timing in performing procedure steps, situation

  7. A study on method to identify actual causes and conditions of safety rule deviations through analyzing events due to unsafe acts of workers

    International Nuclear Information System (INIS)

    Hirotsu, Yuko; Takeda, Daisuke

    2010-01-01

    The purpose of this study is to establish a method to understand actual causes and condition of intentional deviation from safety rules (including norm and written rules that has developed to anticipate, prevent, detect and recover human errors) in an organization by analyzing events due to unsafe acts of workers (human factor events) and to propose effective measures. Firstly, by reviewing literature regarding safety violations, the following two advantages of investigating actual condition of safety rule deviation through human factor event analysis were extracted, such as (a) being able to clarify relationships between deviations, human errors, and events, and (b) being able to identify specific causal factors that influenced the decision to deviate, including acts of people concerned, problems with rules, task demands, environment and management. Next, through the analysis of human factor event data in accordance with existing human error analysis method on the basis of advantages above, the following three requirements for analyzing event data were extracted, such as (a) gathering information such as rules concerning to the work activities related to the human factor events, and whether there are intentional deviations of the rules, (b) gathering information and identify interrelations among causal factors of the intentional deviations, and (c) gathering information on general condition of deviations and the causal factors. (author)

  8. Analysis of adverse events occurred at overseas nuclear power plants in 2003

    International Nuclear Information System (INIS)

    Miyazaki, Takamasa; Sato, Masahiro; Takagawa, Kenichi; Fushimi, Yasuyuki; Shimada, Hiroki; Shimada, Yoshio

    2004-01-01

    The adverse events that have occurred in the overseas nuclear power plants can be studied to provide an indication of how to improve the safety and the reliability of nuclear power plants in Japan. The Institute of Nuclear Safety Systems (INSS) obtains information related to overseas adverse events and incidents, and by evaluating them proposes improvements to prevent similar occurrences in Japanese PWR plants. In 2003, INSS obtained approximately 2800 pieces of information and, by evaluating them, proposed nine recommendations to Japanese utilities. This report shows a summary of the evaluation activity and of the tendency analysis based on individual event analyzed in 2003. The tendency analysis was undertaken on about 1600 analyzed events, from the view point of Mechanics, Electrics, Instruments and Controls and Operations, about the causes, countermeasures, troubled equipments and the possible of lessons learnt from overseas events. This report is to show the whole tendency of overseas events and incidents for the improvement of the safety and reliability of domestic PWR plants. (author)

  9. Identification and analysis of external event combinations for Hanhikivi 1PRA

    Energy Technology Data Exchange (ETDEWEB)

    Helander, Juho [Fennovoima Oy, Helsinki (Finland)

    2017-03-15

    Fennovoima's nuclear power plant, Hanhikivi 1, Pyhäjoki, Finland, is currently in design phase, and its construction is scheduled to begin in 2018 and electricity production in 2024. The objective of this paper is to produce a preliminary list of safety-significant external event combinations including preliminary probability estimates, to be used in the probabilistic risk assessment of Hanhikivi 1 plant. Starting from the list of relevant single events, the relevant event combinations are identified based on seasonal variation, preconditions related to different events, and dependencies (fundamental and cascade type) between events. Using this method yields 30 relevant event combinations of two events for the Hanhikivi site. The preliminary probability of each combination is evaluated, and event combinations with extremely low probability are excluded from further analysis. Event combinations of three or more events are identified by adding possible events to the remaining combinations of two events. Finally, 10 relevant combinations of two events and three relevant combinations of three events remain. The results shall be considered preliminary and will be updated after evaluating more detailed effects of different events on plant safety.

  10. Humans can integrate feedback of discrete events in their sensorimotor control of a robotic hand.

    Science.gov (United States)

    Cipriani, Christian; Segil, Jacob L; Clemente, Francesco; ff Weir, Richard F; Edin, Benoni

    2014-11-01

    Providing functionally effective sensory feedback to users of prosthetics is a largely unsolved challenge. Traditional solutions require high band-widths for providing feedback for the control of manipulation and yet have been largely unsuccessful. In this study, we have explored a strategy that relies on temporally discrete sensory feedback that is technically simple to provide. According to the Discrete Event-driven Sensory feedback Control (DESC) policy, motor tasks in humans are organized in phases delimited by means of sensory encoded discrete mechanical events. To explore the applicability of DESC for control, we designed a paradigm in which healthy humans operated an artificial robot hand to lift and replace an instrumented object, a task that can readily be learned and mastered under visual control. Assuming that the central nervous system of humans naturally organizes motor tasks based on a strategy akin to DESC, we delivered short-lasting vibrotactile feedback related to events that are known to forcefully affect progression of the grasp-lift-and-hold task. After training, we determined whether the artificial feedback had been integrated with the sensorimotor control by introducing short delays and we indeed observed that the participants significantly delayed subsequent phases of the task. This study thus gives support to the DESC policy hypothesis. Moreover, it demonstrates that humans can integrate temporally discrete sensory feedback while controlling an artificial hand and invites further studies in which inexpensive, noninvasive technology could be used in clever ways to provide physiologically appropriate sensory feedback in upper limb prosthetics with much lower band-width requirements than with traditional solutions.

  11. Microprocessor event analysis in parallel with Camac data acquisition

    International Nuclear Information System (INIS)

    Cords, D.; Eichler, R.; Riege, H.

    1981-01-01

    The Plessey MIPROC-16 microprocessor (16 bits, 250 ns execution time) has been connected to a Camac System (GEC-ELLIOTT System Crate) and shares the Camac access with a Nord-1OS computer. Interfaces have been designed and tested for execution of Camac cycles, communication with the Nord-1OS computer and DMA-transfer from Camac to the MIPROC-16 memory. The system is used in the JADE data-acquisition-system at PETRA where it receives the data from the detector in parallel with the Nord-1OS computer via DMA through the indirect-data-channel mode. The microprocessor performs an on-line analysis of events and the result of various checks is appended to the event. In case of spurious triggers or clear beam gas events, the Nord-1OS buffer will be reset and the event omitted from further processing. (orig.)

  12. The human impact of tsunamis: a historical review of events 1900-2009 and systematic literature review.

    Science.gov (United States)

    Doocy, Shannon; Daniels, Amy; Dick, Anna; Kirsch, Thomas D

    2013-04-16

    Introduction. Although rare, tsunamis have the potential to cause considerable loss of life and injury as well as widespread damage to the natural and built environments. The objectives of this review were to describe the impact of tsunamis on human populations in terms of mortality, injury, and displacement and, to the extent possible, identify risk factors associated with these outcomes. This is one of five reviews on the human impact of natural disasters. Methods. Data on the impact of tsunamis were compiled using two methods, a historical review from 1900 to mid 2009 of tsunami events from multiple databases and a systematic literature review to October 2012 of publications. Analysis included descriptive statistics and bivariate tests for associations between tsunami mortality and characteristics using STATA 11. Findings. There were 255,195 deaths (range 252,619-275,784) and 48,462 injuries (range 45,466-51,457) as a result of tsunamis from 1900 to 2009. The majority of deaths (89%) and injuries reported during this time period were attributed to a single event -the 2004 Indian Ocean tsunami. Findings from the systematic literature review indicate that the primary cause of tsunami-related mortality is drowning, and that females, children and the elderly are at increased mortality risk. The few studies that reported on tsunami-related injury suggest that males and young adults are at increased injury-risk. Conclusions. Early warning systems may help mitigate tsunami-related loss of life.

  13. Using discriminant analysis as a nucleation event classification method

    Directory of Open Access Journals (Sweden)

    S. Mikkonen

    2006-01-01

    Full Text Available More than three years of measurements of aerosol size-distribution and different gas and meteorological parameters made in Po Valley, Italy were analysed for this study to examine which of the meteorological and trace gas variables effect on the emergence of nucleation events. As the analysis method, we used discriminant analysis with non-parametric Epanechnikov kernel, included in non-parametric density estimation method. The best classification result in our data was reached with the combination of relative humidity, ozone concentration and a third degree polynomial of radiation. RH appeared to have a preventing effect on the new particle formation whereas the effects of O3 and radiation were more conductive. The concentration of SO2 and NO2 also appeared to have significant effect on the emergence of nucleation events but because of the great amount of missing observations, we had to exclude them from the final analysis.

  14. Survival analysis using S analysis of time-to-event data

    CERN Document Server

    Tableman, Mara

    2003-01-01

    Survival Analysis Using S: Analysis of Time-to-Event Data is designed as a text for a one-semester or one-quarter course in survival analysis for upper-level or graduate students in statistics, biostatistics, and epidemiology. Prerequisites are a standard pre-calculus first course in probability and statistics, and a course in applied linear regression models. No prior knowledge of S or R is assumed. A wide choice of exercises is included, some intended for more advanced students with a first course in mathematical statistics. The authors emphasize parametric log-linear models, while also detailing nonparametric procedures along with model building and data diagnostics. Medical and public health researchers will find the discussion of cut point analysis with bootstrap validation, competing risks and the cumulative incidence estimator, and the analysis of left-truncated and right-censored data invaluable. The bootstrap procedure checks robustness of cut point analysis and determines cut point(s). In a chapter ...

  15. Tendencies in human factor influence on initiating events occurrence in NPP Kozloduy

    International Nuclear Information System (INIS)

    Hristova, R.

    2001-01-01

    Overview of the methods and documents concerning human factor in nuclear safety and selection of the most appropriate methods and concept for human factor assessment in the reported events in Kozloduy NPP are presented. List of human error types and statistical data (the mean time between similar errors, the human rate λ, the number of occurrences ect.) is given. Some general results from the human error behavior investigation for all units of Kozloduy NPP related to the 4 personnel categories: Management personnel, Designers, Operating personnel, Maintenance personnel are also shown. At the end the following conclusion are made:18 % operating personnel errors (for comparison for the same category personnel in similar NPPs abroad this value is between 10 % and 30%); Human errors in Kozloduy NPP tend to increase after year 1990; only for the operating personnel a maximum near year 1997 was observed, after which the error values was decreased; at the beginning of year 2000 the reliability characteristics for all units have similar values; it is necessary to be taken into account the observed tendencies to take measurements for reducing of the most important error types for Kozloduy NPP personnel

  16. Analysis of geohazards events along Swiss roads from autumn 2011 to present

    Science.gov (United States)

    Voumard, Jérémie; Jaboyedoff, Michel; Derron, Marc-Henri

    2014-05-01

    In Switzerland, roads and railways are threatened throughout the year by several natural hazards. Some of these events reach transport infrastructure many time per year leading to the closing of transportation corridors, loss of access, deviation travels and sometimes infrastructures damages and loss of human lives (3 fatalities during the period considered). The aim of this inventory of events is to investigate the number of natural events affecting roads and railways in Switzerland since autumn 2011 until now. Natural hazards affecting roads and railway can be classified in five categories: rockfalls, landslides, debris flows, snow avalanches and floods. They potentially cause several important direct damages on transportation infrastructure (roads, railway), vehicles (slightly or very damaged) or human life (slightly or seriously injured person, death). These direct damages can be easily evaluated from press articles or from Swiss police press releases. Indirect damages such as deviation cost are not taken into account in this work. During the two a half last years, about 50 events affecting the Swiss roads and Swiss railways infrastructures were inventoried. The proportion of events due to rockfalls is 45%, to landslides 25%, to debris flows 15%, to snow avalanches 10% and to floods 5%. During this period, three fatalities and two persons were injured while 23 vehicles (car, trains and coach) and 24 roads and railways were damaged. We can see that floods occur mainly on the Swiss Plateau whereas rockfalls, debris flow, snow avalanches and landslides are mostly located in the Alpine area. Most of events occur on secondary mountain roads and railways. The events are well distributed on the whole Alpine area except for the Gotthard hotspot, where an important European North-South motorway (hit in 2003 with two fatalities) and railway (hit three times in 2012 with one fatalities) are more frequently affected. According to the observed events in border regions of

  17. Event tree analysis using artificial intelligence techniques

    International Nuclear Information System (INIS)

    Dixon, B.W.; Hinton, M.F.

    1985-01-01

    Artificial Intelligence (AI) techniques used in Expert Systems and Object Oriented Programming are discussed as they apply to Event Tree Analysis. A SeQUence IMPortance calculator, SQUIMP, is presented to demonstrate the implementation of these techniques. Benefits of using AI methods include ease of programming, efficiency of execution, and flexibility of application. The importance of an appropriate user interface is stressed. 5 figs

  18. Verification of Large State/Event Systems using Compositionality and Dependency Analysis

    DEFF Research Database (Denmark)

    Lind-Nielsen, Jørn; Andersen, Henrik Reif; Hulgaard, Henrik

    2001-01-01

    A state/event model is a concurrent version of Mealy machines used for describing embedded reactive systems. This paper introduces a technique that uses compositionality and dependency analysis to significantly improve the efficiency of symbolic model checking of state/event models. It makes...

  19. Verification of Large State/Event Systems using Compositionality and Dependency Analysis

    DEFF Research Database (Denmark)

    Lind-Nielsen, Jørn; Andersen, Henrik Reif; Behrmann, Gerd

    1999-01-01

    A state/event model is a concurrent version of Mealy machines used for describing embedded reactive systems. This paper introduces a technique that uses \\emph{compositionality} and \\emph{dependency analysis} to significantly improve the efficiency of symbolic model checking of state/event models...

  20. Analysis of nuclear and radiological events. Textbook for lecture in graduate school of engineering in the University of Tokyo

    International Nuclear Information System (INIS)

    Watanabe, Norio

    2007-02-01

    The Japan Atomic Energy Agency is carrying out the cooperative activity by providing specialized educational and training staff and making our facilities available for the graduate school of engineering in The University of Tokyo as part of developing human resources in nuclear technology. This report is prepared as a textbook for the lecture in the graduate school of engineering in The University of Tokyo and provides the outlines of activities on the analysis of nuclear and radiological events and analysis methods as well as the summaries of major incidents and accidents that occurred. (author)

  1. Time Based Workload Analysis Method for Safety-Related Operator Actions in Safety Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yun Goo; Oh, Eung Se [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2016-05-15

    During the design basis event, the safety system performs safety functions to mitigate the event. The most of safety system is actuated by automatic system however, there are operator manual actions that are needed for the plant safety. These operator actions are classified as important human actions in human factors engineering design. The human factors engineering analysis and evaluation is needed for these important human actions to assure that operator successfully perform their tasks for plant safety and operational goals. The work load analysis is one of the required analysis for the important human actions.

  2. Time Based Workload Analysis Method for Safety-Related Operator Actions in Safety Analysis

    International Nuclear Information System (INIS)

    Kim, Yun Goo; Oh, Eung Se

    2016-01-01

    During the design basis event, the safety system performs safety functions to mitigate the event. The most of safety system is actuated by automatic system however, there are operator manual actions that are needed for the plant safety. These operator actions are classified as important human actions in human factors engineering design. The human factors engineering analysis and evaluation is needed for these important human actions to assure that operator successfully perform their tasks for plant safety and operational goals. The work load analysis is one of the required analysis for the important human actions.

  3. Ultimate design load analysis of planetary gearbox bearings under extreme events

    DEFF Research Database (Denmark)

    Gallego Calderon, Juan Felipe; Natarajan, Anand; Cutululis, Nicolaos Antonio

    2017-01-01

    This paper investigates the impact of extreme events on the planet bearings of a 5 MW gearbox. The system is simulated using an aeroelastic tool, where the turbine structure is modeled, and MATLAB/Simulink, where the drivetrain (gearbox and generator) are modeled using a lumped-parameter approach....... Three extreme events are assessed: low-voltage ride through, emergency stop and normal stop. The analysis is focused on finding which event has the most negative impact on the bearing extreme radial loads. The two latter events are carried out following the guidelines of the International...

  4. Analysis of human reliability in the APS of fire. Application of NUREG-1921; Analisis de Fiabilidad Humana en el APS de Incendios. Aplicacion del NUREG-1921

    Energy Technology Data Exchange (ETDEWEB)

    Perez Torres, J. L.; Celaya Meler, M. A.

    2014-07-01

    An analysis of human reliability in a probabilistic safety analysis (APS) of fire aims to identify, describe, analyze and quantify, in a manner traceable, human actions that can affect the mitigation of an initiating event produced by a fire. (Author)

  5. Analysis of unprotected overcooling events in the Integral Fast Reactor

    International Nuclear Information System (INIS)

    Vilim, R.B.

    1989-01-01

    Simple analytic models are developed for predicting the response of a metal fueled, liquid-metal cooled reactor to unprotected overcooling events in the balance of plant. All overcooling initiators are shown to fall into two categories. The first category contains these events for which there is no final equilibrium state of constant overcooling, as in the case for a large steam leak. These events are analyzed using a non-flow control mass approach. The second category contains those events which will eventually equilibrate, such as a loss of feedwater heaters. A steady flow control volume analysis shows that these latter events ultimately affect the plant through the feedwater inlet to the steam generator. The models developed for analyzing these two categories provide upper bounds for the reactor's passive response to overcooling accident initiators. Calculation of these bounds for a prototypic plant indicate that failure limits -- eutectic melting, sodium boiling, fuel pin failure -- are not exceeded in any overcooling event. 2 refs

  6. Microprocessor event analysis in parallel with CAMAC data acquisition

    CERN Document Server

    Cords, D; Riege, H

    1981-01-01

    The Plessey MIPROC-16 microprocessor (16 bits, 250 ns execution time) has been connected to a CAMAC System (GEC-ELLIOTT System Crate) and shares the CAMAC access with a Nord-10S computer. Interfaces have been designed and tested for execution of CAMAC cycles, communication with the Nord-10S computer and DMA-transfer from CAMAC to the MIPROC-16 memory. The system is used in the JADE data-acquisition-system at PETRA where it receives the data from the detector in parallel with the Nord-10S computer via DMA through the indirect-data-channel mode. The microprocessor performs an on-line analysis of events and the results of various checks is appended to the event. In case of spurious triggers or clear beam gas events, the Nord-10S buffer will be reset and the event omitted from further processing. (5 refs).

  7. Regression analysis of mixed panel count data with dependent terminal events.

    Science.gov (United States)

    Yu, Guanglei; Zhu, Liang; Li, Yang; Sun, Jianguo; Robison, Leslie L

    2017-05-10

    Event history studies are commonly conducted in many fields, and a great deal of literature has been established for the analysis of the two types of data commonly arising from these studies: recurrent event data and panel count data. The former arises if all study subjects are followed continuously, while the latter means that each study subject is observed only at discrete time points. In reality, a third type of data, a mixture of the two types of the data earlier, may occur and furthermore, as with the first two types of the data, there may exist a dependent terminal event, which may preclude the occurrences of recurrent events of interest. This paper discusses regression analysis of mixed recurrent event and panel count data in the presence of a terminal event and an estimating equation-based approach is proposed for estimation of regression parameters of interest. In addition, the asymptotic properties of the proposed estimator are established, and a simulation study conducted to assess the finite-sample performance of the proposed method suggests that it works well in practical situations. Finally, the methodology is applied to a childhood cancer study that motivated this study. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  8. A novel human ex vivo model for the analysis of molecular events during lung cancer chemotherapy

    Directory of Open Access Journals (Sweden)

    Lang Dagmar S

    2007-06-01

    Full Text Available Abstract Background Non-small cell lung cancer (NSCLC causes most of cancer related deaths in humans and is characterized by poor prognosis regarding efficiency of chemotherapeutical treatment and long-term survival of the patients. The purpose of the present study was the development of a human ex vivo tissue culture model and the analysis of the effects of conventional chemotherapy, which then can serve as a tool to test new chemotherapeutical regimens in NSCLC. Methods In a short-term tissue culture model designated STST (Short-Term Stimulation of Tissues in combination with the novel *HOPE-fixation and paraffin embedding method we examined the responsiveness of 41 human NSCLC tissue specimens to the individual cytotoxic drugs carboplatin, vinorelbine or gemcitabine. Viability was analyzed by LIFE/DEAD assay, TUNEL-staining and colorimetric MTT assay. Expression of Ki-67 protein and of BrdU (bromodeoxyuridine uptake as markers for proliferation and of cleaved (activated effector caspase-3 as indicator of late phase apoptosis were assessed by immunohistochemistry. Transcription of caspase-3 was analyzed by RT-PCR. Flow cytometry was utilized to determine caspase-3 in human cancer cell lines. Results Viability, proliferation and apoptosis of the tissues were moderately affected by cultivation. In human breast cancer, small-cell lung cancer (SCLC and human cell lines (CPC-N, HEK proliferative capacity was clearly reduced by all 3 chemotherapeutic agents in a very similar manner. Cleavage of caspase-3 was induced in the chemo-sensitive types of cancer (breast cancer, SCLC. Drug-induced effects in human NSCLC tissues were less evident than in the chemo-sensitive tumors with more pronounced effects in adenocarcinomas as compared to squamous cell carcinomas. Conclusion Although there was high heterogeneity among the individual tumor tissue responses as expected, we clearly demonstrate specific multiple drug-induced effects simultaneously. Thus, STST

  9. Balboa: A Framework for Event-Based Process Data Analysis

    National Research Council Canada - National Science Library

    Cook, Jonathan E; Wolf, Alexander L

    1998-01-01

    .... We have built Balboa as a bridge between the data collection and the analysis tools, facilitating the gathering and management of event data, and simplifying the construction of tools to analyze the data...

  10. External human induced events in site evaluation for nuclear power plants. Safety guide

    International Nuclear Information System (INIS)

    2004-01-01

    The purpose of the present Safety Guide is to provide recommendations and guidance for the examination of the region considered for site evaluation for a plant in order to identity hazardous phenomena associated with human induced events initiated by sources external to the plant. In some cases it also presents preliminary guidance for deriving values of relevant parameters for the design basis. This Safety Guide is also applicable for periodic site evaluation and site evaluation following a major human induced event, and for the design and operation of the site's environmental monitoring system. Site evaluation includes site characterization. Consideration of external events that could lead to a degradation of the safety features of the plant and cause a release of radioactive material from the plant and/or affect the dispersion of such material in the environment. And consideration of population issues and access issues significant to safety (such as the feasibility of evacuation, the population distribution and the location of resources). The process of site evaluation continues throughout the lifetime of the facility, from siting to design, construction, operation and decommissioning. The external human induced events considered in this Safety Guide are all of accidental origin. Considerations relating to the physical protection of the plant against wilful actions by third parties are outside its scope. However, the methods described herein may also have some application for the purposes of such physical protection. The present Safety Guide may also be used for events that may originate within the boundaries of the site, but from sources which are not directly involved in the operational states of the nuclear power plant units, such as fuel depots or areas for the storage of hazardous materials for the construction of other facilities at the same site. Special consideration should be given to the hazardous material handled during the construction, operation and

  11. Arenal-type pyroclastic flows: A probabilistic event tree risk analysis

    Science.gov (United States)

    Meloy, Anthony F.

    2006-09-01

    A quantitative hazard-specific scenario-modelling risk analysis is performed at Arenal volcano, Costa Rica for the newly recognised Arenal-type pyroclastic flow (ATPF) phenomenon using an event tree framework. These flows are generated by the sudden depressurisation and fragmentation of an active basaltic andesite lava pool as a result of a partial collapse of the crater wall. The deposits of this type of flow include angular blocks and juvenile clasts, which are rarely found in other types of pyroclastic flow. An event tree analysis (ETA) is a useful tool and framework in which to analyse and graphically present the probabilities of the occurrence of many possible events in a complex system. Four event trees are created in the analysis, three of which are extended to investigate the varying individual risk faced by three generic representatives of the surrounding community: a resident, a worker, and a tourist. The raw numerical risk estimates determined by the ETA are converted into a set of linguistic expressions (i.e. VERY HIGH, HIGH, MODERATE etc.) using an established risk classification scale. Three individually tailored semi-quantitative risk maps are then created from a set of risk conversion tables to show how the risk varies for each individual in different areas around the volcano. In some cases, by relocating from the north to the south, the level of risk can be reduced by up to three classes. While the individual risk maps may be broadly applicable, and therefore of interest to the general community, the risk maps and associated probability values generated in the ETA are intended to be used by trained professionals and government agencies to evaluate the risk and effectively manage the long-term development of infrastructure and habitation. With the addition of fresh monitoring data, the combination of both long- and short-term event trees would provide a comprehensive and consistent method of risk analysis (both during and pre-crisis), and as such

  12. Analysis of internal events for the Unit 1 of the Laguna Verde nuclear power station

    International Nuclear Information System (INIS)

    Huerta B, A.; Aguilar T, O.; Nunez C, A.; Lopez M, R.

    1993-01-01

    This volume presents the results of the starter event analysis and the event tree analysis for the Unit 1 of the Laguna Verde nuclear power station. The starter event analysis includes the identification of all those internal events which cause a disturbance to the normal operation of the power station and require mitigation. Those called external events stay beyond the reach of this study. For the analysis of the Laguna Verde power station eight transient categories were identified, three categories of loss of coolant accidents (LOCA) inside the container, a LOCA out of the primary container, as well as the vessel break. The event trees analysis involves the development of the possible accident sequences for each category of starter events. Events trees by systems for the different types of LOCA and for all the transients were constructed. It was constructed the event tree for the total loss of alternating current, which represents an extension of the event tree for the loss of external power transient. Also the event tree by systems for the anticipated transients without scram was developed (ATWS). The events trees for the accident sequences includes the sequences evaluation with vulnerable nucleus, that is to say those sequences in which it is had an adequate cooling of nucleus but the remoting systems of residual heat had failed. In order to model adequately the previous, headings were added to the event tree for developing the sequences until the point where be solved the nucleus state. This process includes: the determination of the failure pressure of the primary container, the evaluation of the environment generated in the reactor building as result of the container failure or cracked of itself, the determination of the localization of the components in the reactor building and the construction of boolean expressions to estimate the failure of the subordinated components to an severe environment. (Author)

  13. Phylogenetic analysis and victim contact tracing of rabies virus from humans and dogs in Bali, Indonesia.

    Science.gov (United States)

    Mahardika, G N K; Dibia, N; Budayanti, N S; Susilawathi, N M; Subrata, K; Darwinata, A E; Wignall, F S; Richt, J A; Valdivia-Granda, W A; Sudewi, A A R

    2014-06-01

    The emergence of human and animal rabies in Bali since November 2008 has attracted local, national and international interest. The potential origin and time of introduction of rabies virus to Bali is described. The nucleoprotein (N) gene of rabies virus from dog brain and human clinical specimens was sequenced using an automated DNA sequencer. Phylogenetic inference with Bayesian Markov Chain Monte Carlo (MCMC) analysis using the Bayesian Evolutionary Analysis by Sampling Trees (BEAST) v. 1.7.5 software confirmed that the outbreak of rabies in Bali was caused by an Indonesian lineage virus following a single introduction. The ancestor of Bali viruses was the descendant of a virus from Kalimantan. Contact tracing showed that the event most likely occurred in early 2008. The introduction of rabies into a large unvaccinated dog population in Bali clearly demonstrates the risk of disease transmission for government agencies and should lead to an increased preparedness and efforts for sustained risk reduction to prevent such events from occurring in future.

  14. Markov chains and semi-Markov models in time-to-event analysis.

    Science.gov (United States)

    Abner, Erin L; Charnigo, Richard J; Kryscio, Richard J

    2013-10-25

    A variety of statistical methods are available to investigators for analysis of time-to-event data, often referred to as survival analysis. Kaplan-Meier estimation and Cox proportional hazards regression are commonly employed tools but are not appropriate for all studies, particularly in the presence of competing risks and when multiple or recurrent outcomes are of interest. Markov chain models can accommodate censored data, competing risks (informative censoring), multiple outcomes, recurrent outcomes, frailty, and non-constant survival probabilities. Markov chain models, though often overlooked by investigators in time-to-event analysis, have long been used in clinical studies and have widespread application in other fields.

  15. Operating experience feedback from safety significant events at research reactors

    Energy Technology Data Exchange (ETDEWEB)

    Shokr, A.M. [Atomic Energy Authority, Abouzabal (Egypt). Egypt Second Research Reactor; Rao, D. [Bhabha Atomic Research Centre, Mumbai (India)

    2015-05-15

    Operating experience feedback is an effective mechanism to provide lessons learned from the events and the associated corrective actions to prevent recurrence of events, resulting in improving safety in the nuclear installations. This paper analyzes the events of safety significance that have been occurred at research reactors and discusses the root causes and lessons learned from these events. Insights from literature on events at research reactors and feedback from events at nuclear power plants that are relevant to research reactors are also presented along with discussions. The results of the analysis showed the importance of communication of safety information and exchange of operating experience are vital to prevent reoccurrences of events. The analysis showed also the need for continued attention to human factors and training of operating personnel, and the need for establishing systematic ageing management programmes of reactor facilities, and programmes for safety management of handling of nuclear fuel, core components, and experimental devices.

  16. Operating experience feedback from safety significant events at research reactors

    International Nuclear Information System (INIS)

    Shokr, A.M.

    2015-01-01

    Operating experience feedback is an effective mechanism to provide lessons learned from the events and the associated corrective actions to prevent recurrence of events, resulting in improving safety in the nuclear installations. This paper analyzes the events of safety significance that have been occurred at research reactors and discusses the root causes and lessons learned from these events. Insights from literature on events at research reactors and feedback from events at nuclear power plants that are relevant to research reactors are also presented along with discussions. The results of the analysis showed the importance of communication of safety information and exchange of operating experience are vital to prevent reoccurrences of events. The analysis showed also the need for continued attention to human factors and training of operating personnel, and the need for establishing systematic ageing management programmes of reactor facilities, and programmes for safety management of handling of nuclear fuel, core components, and experimental devices.

  17. Trend analysis of breaker events at United States nuclear power plants

    International Nuclear Information System (INIS)

    Shimada, Hiroki

    2006-01-01

    From events in overseas nuclear power plants recorded in the nuclear information detabase of Institute of Nuclear Safety System, Inc. (INSS), the number of events of electrical systems during the four years from 2002 to 2005 was extracted and the trend was analyzed. The results showed that breaker events were the largest in number in all years, and almost all them occurred in the US. The breaker events that occurred in US nuclear power plants in 2005 were analyzed by classifying them by cause of failure and effect on the plant, and by comparing the number of occurrences with that in Japan. As a result, the main cause of many of the breaker events was improper maintenance due to poor arrangement of maintenance manuals and human error, as well as aging degradation, they can be estimated to have been caused by insufficient maintenance control and inspection. The number of breaker failures per plant per year in our country was lower than that in the US by an order of magnitude, and there were no failures that led to a plant trip or power reduction. These facts suggest that our country's maintenance contents of breaker are advantage. (author)

  18. Serological analysis of human anti-human antibody responses in colon cancer patients treated with repeated doses of humanized monoclonal antibody A33.

    Science.gov (United States)

    Ritter, G; Cohen, L S; Williams, C; Richards, E C; Old, L J; Welt, S

    2001-09-15

    Mouse monoclonal antibody A33 (mAb A33) recognizes a M(r) 43,000 cell surface glycoprotein (designated A33) expressed in human colonic epithelium and colon cancer but absent from most other normal tissues. In patients, mAb A33 localizes with high specificity to colon cancer and is retained for up to 6 weeks in the cancer but cleared rapidly from normal colon (5-6 days). As a carrier of (125)I or (131)I, mAb A33 has shown antitumor activity. Induction of strong human anti-mouse antibody (immunoglobulin; HAMA) responses in patients, however, limits the use of the murine mAb A33 to very few injections. A humanized version of this antibody (huAb A33) has been prepared for Phase I and II clinical studies in patients with colon cancer. In those studies, immunogenicity of huAb A33 has been monitored using a novel, highly sensitive BIACORE method, which allows measurement of human anti-human antibodies (HAHAs) without the use of secondary reagents. We found that 63% (26 of 41) of the patients treated with repeated doses of huAb A33 developed HAHAs against a conformational antigenic determinant located in the V(L) and V(H) regions of huAb A33. Detailed serological analysis showed two distinct types of HAHAs. HAHA of type I (49% of patients) was characterized by an early onset with peak HAHA levels after 2 weeks of treatment, which declined with ongoing huAb A33 treatment. HAHA of type II (17% of patients) was characterized by a typically later onset of HAHA than in type I and by progressively increasing HAHA levels with each subsequent huAb A33 administration. Colon cancer patients with type I HAHAs did not develop infusion-related adverse events. In contrast, HAHA of type II was indicative of infusion-related adverse events. By using this new method, we were able to distinguish these two types of HAHAs in patients while on antibody treatment, allowing patients to be removed from study prior to the onset of severe infusion-related adverse events.

  19. Human factors assessment in PRA using task analysis linked evaluation technique (TALENT)

    International Nuclear Information System (INIS)

    Wells, J.E.; Banks, W.W.

    1990-01-01

    Human error is a primary contributor to risk in complex high-reliability systems. A 1985 U.S. Nuclear Regulatory Commission (USNRC) study of licensee event reports (LERs) suggests that upwards of 65% of commercial nuclear system failures involve human error. Since then, the USNRC has initiated research to fully and properly integrate human errors into the probabilistic risk assessment (PRA) process. The resulting implementation procedure is known as the Task Analysis Linked Evaluation Technique (TALENT). As indicated, TALENT is a broad-based method for integrating human factors expertise into the PRA process. This process achieves results which: (1) provide more realistic estimates of the impact of human performance on nuclear power safety, (2) can be fully audited, (3) provide a firm technical base for equipment-centered and personnel-centered retrofit/redesign of plants enabling them to meet internally and externally imposed safety standards, and (4) yield human and hardware data capable of supporting inquiries into human performance issues that transcend the individual plant. The TALENT procedure is being field-tested to verify its effectiveness and utility. The objectives of the field-test are to examine (1) the operability of the process, (2) its acceptability to the users, and (3) its usefulness for achieving measurable improvements in the credibility of the analysis. The field-test will provide the information needed to enhance the TALENT process

  20. Evidence of molecular evolution driven by recombination events influencing tropism in a novel human adenovirus that causes epidemic keratoconjunctivitis.

    Directory of Open Access Journals (Sweden)

    Michael P Walsh

    2009-06-01

    Full Text Available In 2005, a human adenovirus strain (formerly known as HAdV-D22/H8 but renamed here HAdV-D53 was isolated from an outbreak of epidemic keratoconjunctititis (EKC, a disease that is usually caused by HAdV-D8, -D19, or -D37, not HAdV-D22. To date, a complete change of tropism compared to the prototype has never been observed, although apparent recombinant strains of other viruses from species Human adenovirus D (HAdV-D have been described. The complete genome of HAdV-D53 was sequenced to elucidate recombination events that lead to the emergence of a viable and highly virulent virus with a modified tropism. Bioinformatic and phylogenetic analyses of this genome demonstrate that this adenovirus is a recombinant of HAdV-D8 (including the fiber gene encoding the primary cellular receptor binding site, HAdV-D22, (the epsilon determinant of the hexon gene, HAdV-D37 (including the penton base gene encoding the secondary cellular receptor binding site, and at least one unknown or unsequenced HAdV-D strain. Bootscanning analysis of the complete genomic sequence of this novel adenovirus, which we have re-named HAdV-D53, indicated at least five recombination events between the aforementioned adenoviruses. Intrahexon recombination sites perfectly framed the epsilon neutralization determinant that was almost identical to the HAdV-D22 prototype. Additional bootscan analysis of all HAdV-D hexon genes revealed recombinations in identical locations in several other adenoviruses. In addition, HAdV-D53 but not HAdV-D22 induced corneal inflammation in a mouse model. Serological analysis confirmed previous results and demonstrated that HAdV-D53 has a neutralization profile representative of the epsilon determinant of its hexon (HAdV-D22 and the fiber (HAdV-D8 proteins. Our recombinant hexon sequence is almost identical to the hexon sequences of the HAdV-D strain causing EKC outbreaks in Japan, suggesting that HAdV-D53 is pandemic as an emerging EKC agent. This documents

  1. User's manual of a support system for human reliability analysis

    International Nuclear Information System (INIS)

    Yokobayashi, Masao; Tamura, Kazuo.

    1995-10-01

    Many kinds of human reliability analysis (HRA) methods have been developed. However, users are required to be skillful so as to use them, and also required complicated works such as drawing event tree (ET) and calculation of uncertainty bounds. Moreover, each method is not so complete that only one method of them is not enough to evaluate human reliability. Therefore, a personal computer (PC) based support system for HRA has been developed to execute HRA practically and efficiently. The system consists of two methods, namely, simple method and detailed one. The former uses ASEP that is a simplified THERP-technique, and combined method of OAT and HRA-ET/DeBDA is used for the latter. Users can select a suitable method for their purpose. Human error probability (HEP) data were collected and a database of them was built to use for the support system. This paper describes outline of the HRA methods, support functions and user's guide of the system. (author)

  2. Feature Extraction of Event-Related Potentials Using Wavelets: An Application to Human Performance Monitoring

    Science.gov (United States)

    Trejo, Leonard J.; Shensa, Mark J.; Remington, Roger W. (Technical Monitor)

    1998-01-01

    This report describes the development and evaluation of mathematical models for predicting human performance from discrete wavelet transforms (DWT) of event-related potentials (ERP) elicited by task-relevant stimuli. The DWT was compared to principal components analysis (PCA) for representation of ERPs in linear regression and neural network models developed to predict a composite measure of human signal detection performance. Linear regression models based on coefficients of the decimated DWT predicted signal detection performance with half as many f ree parameters as comparable models based on PCA scores. In addition, the DWT-based models were more resistant to model degradation due to over-fitting than PCA-based models. Feed-forward neural networks were trained using the backpropagation,-, algorithm to predict signal detection performance based on raw ERPs, PCA scores, or high-power coefficients of the DWT. Neural networks based on high-power DWT coefficients trained with fewer iterations, generalized to new data better, and were more resistant to overfitting than networks based on raw ERPs. Networks based on PCA scores did not generalize to new data as well as either the DWT network or the raw ERP network. The results show that wavelet expansions represent the ERP efficiently and extract behaviorally important features for use in linear regression or neural network models of human performance. The efficiency of the DWT is discussed in terms of its decorrelation and energy compaction properties. In addition, the DWT models provided evidence that a pattern of low-frequency activity (1 to 3.5 Hz) occurring at specific times and scalp locations is a reliable correlate of human signal detection performance.

  3. Human errors during the simulations of an SGTR scenario: Application of the HERA system

    International Nuclear Information System (INIS)

    Jung, Won Dea; Whaley, April M.; Hallbert, Bruce P.

    2009-01-01

    Due to the need of data for a Human Reliability Analysis (HRA), a number of data collection efforts have been undertaken in several different organizations. As a part of this effort, a human error analysis that focused on a set of simulator records on a Steam Generator Tube Rupture (SGTR) scenario was performed by using the Human Event Repository and Analysis (HERA) system. This paper summarizes the process and results of the HERA analysis, including discussions about the usability of the HERA system for a human error analysis of simulator data. Five simulated records of an SGTR scenario were analyzed with the HERA analysis process in order to scrutinize the causes and mechanisms of the human related events. From this study, the authors confirmed that the HERA was a serviceable system that can analyze human performance qualitatively from simulator data. It was possible to identify the human related events in the simulator data that affected the system safety not only negatively but also positively. It was also possible to scrutinize the Performance Shaping Factors (PSFs) and the relevant contributory factors with regard to each identified human event

  4. Top event prevention analysis - a deterministic use of PRA

    International Nuclear Information System (INIS)

    Blanchard, D.P.; Worrell, R.B.

    1995-01-01

    Risk importance measures are popular for many applications of probabilistic analysis. Inherent in the derivation of risk importance measures are implicit assumptions that those using these numerical results should be aware of in their decision making. These assumptions and potential limitations include the following: (1) The risk importance measures are derived for a single event at a time and are therefore valid only if all other event probabilities are unchanged at their current values. (2) The results for which risk importance measures are derived may not be complete for reasons such as truncation

  5. Analysis of events occurred at overseas nuclear power plants in 2004

    International Nuclear Information System (INIS)

    Miyazaki, Takamasa; Nishioka, Hiromasa; Sato, Masahiro; Chiba, Gorou; Takagawa, Kenichi; Shimada, Hiroki

    2005-01-01

    The Institute of Nuclear Safety Systems (INSS) investigates the information related to events and incidents occurred at overseas nuclear power plants, and proposes recommendations for the improvement of the safety and reliability of domestic PWR plants by evaluating them. Succeeding to the 2003 report, this report shows the summary of the evaluation activity and of the tendency analysis based on about 2800 information obtained in 2004. The tendency analysis was undertaken on about 1700 analyzed events, from the view point of mechanics, electrics and operations, about the causes, troubled equipments and so on. (author)

  6. [Analysis on the adverse events of cupping therapy in the application].

    Science.gov (United States)

    Zhou, Xin; Ruan, Jing-wen; Xing, Bing-feng

    2014-10-01

    The deep analysis has been done on the cases of adverse events and common injury of cupping therapy encountered in recent years in terms of manipulation and patient's constitution. The adverse events of cupping therapy are commonly caused by improper manipulation of medical practitioners, ignoring contraindication and patient's constitution. Clinical practitioners should use cupping therapy cautiously, follow strictly the rules of standard manipulation and medical core system, pay attention to the contraindication and take strict precautions against the occurrence of adverse events.

  7. Snake scales, partial exposure, and the Snake Detection Theory: A human event-related potentials study

    NARCIS (Netherlands)

    J.W. van Strien (Jan); L.A. Isbell (Lynne A.)

    2017-01-01

    textabstractStudies of event-related potentials in humans have established larger early posterior negativity (EPN) in response to pictures depicting snakes than to pictures depicting other creatures. Ethological research has recently shown that macaques and wild vervet monkeys respond strongly to

  8. A model-based and computer-aided approach to analysis of human errors in nuclear power plants

    International Nuclear Information System (INIS)

    Yoon, Wan C.; Lee, Yong H.; Kim, Young S.

    1996-01-01

    Since the operator's mission in NPPs is increasingly defined by cognitive tasks such as monitoring, diagnosis and planning, the focus of human error analysis should also move from external actions to internal decision-making processes. While more elaborate analysis of cognitive aspects of human errors will help understand their causes and derive effective countermeasures, a lack of framework and an arbitrary resolution of description may hamper the effectiveness of such analysis. This paper presents new model-based schemes of event description and error classification as well as an interactive computerized support system. The schemes and the support system were produced in an effort to develop an improved version of HPES. The use of a decision-making model enables the analyst to document cognitive aspects of human performance explicitly and in a proper resolution. The stage-specific terms used in the proposed schemes make the task of characterizing human errors easier and confident for field analysts. The support system was designed to help the analyst achieve a contextually well-integrated analysis throughout the different parts of HPES

  9. Twitter data analysis: temporal and term frequency analysis with real-time event

    Science.gov (United States)

    Yadav, Garima; Joshi, Mansi; Sasikala, R.

    2017-11-01

    From the past few years, World Wide Web (www) has become a prominent and huge source for user generated content and opinionative data. Among various social media, Twitter gained popularity as it offers a fast and effective way of sharing users’ perspective towards various critical and other issues in different domain. As the data is hugely generated on cloud, it has opened doors for the researchers in the field of data science and analysis. There are various domains such as ‘Political’ domain, ‘Entertainment’ domain and ‘Business’ domain. Also there are various APIs that Twitter provides for developers 1) Search API, focus on the old tweets 2) Rest API, focuses on user details and allow to collect the user profile, friends and followers 3) Streaming API, which collects details like tweets, hashtags, geo locations. In our work we are accessing Streaming API in order to fetch real-time tweets for the dynamic happening event. For this we are focusing on ‘Entertainment’ domain especially ‘Sports’ as IPL-T20 is currently the trending on-going event. We are collecting these numerous amounts of tweets and storing them in MongoDB database where the tweets are stored in JSON document format. On this document we are performing time-series analysis and term frequency analysis using different techniques such as filtering, information extraction for text-mining that fulfils our objective of finding interesting moments for temporal data in the event and finding the ranking among the players or the teams based on popularity which helps people in understanding key influencers on the social media platform.

  10. Development of INSTEC(INformation System of Trip Event Cases)

    International Nuclear Information System (INIS)

    Lee, Jeong Woon; Shim, Bong Sik; Park, Keun Oak; Cheon, Se Woo

    1996-09-01

    In this research, we established an incident analysis procedure based on the concept of interaction between plant components and developed INSTEC(INformation System of Trip Event Cases) which can manage data obtained as the result of incident analysis. The analysis procedure is consisted of the following steps; reconfiguration of incident context, identification of the paths and contents of the interaction between plant components, identification of unit event obstructing normal plant operation, identification of possible erroneous actions, decision of error modes, identification of likely causes, summarization of analysis results. INSTEC was developed to effectively present the result of incident analysis. This system offers the analyzed information such as analysis results of human error cases, operating issues and problems, recommendations to prevent a similar incident, etc. 24 tabs., 18 figs., 10 refs. (Author)

  11. Construction and updating of event models in auditory event processing.

    Science.gov (United States)

    Huff, Markus; Maurer, Annika E; Brich, Irina; Pagenkopf, Anne; Wickelmaier, Florian; Papenmeier, Frank

    2018-02-01

    Humans segment the continuous stream of sensory information into distinct events at points of change. Between 2 events, humans perceive an event boundary. Present theories propose changes in the sensory information to trigger updating processes of the present event model. Increased encoding effort finally leads to a memory benefit at event boundaries. Evidence from reading time studies (increased reading times with increasing amount of change) suggest that updating of event models is incremental. We present results from 5 experiments that studied event processing (including memory formation processes and reading times) using an audio drama as well as a transcript thereof as stimulus material. Experiments 1a and 1b replicated the event boundary advantage effect for memory. In contrast to recent evidence from studies using visual stimulus material, Experiments 2a and 2b found no support for incremental updating with normally sighted and blind participants for recognition memory. In Experiment 3, we replicated Experiment 2a using a written transcript of the audio drama as stimulus material, allowing us to disentangle encoding and retrieval processes. Our results indicate incremental updating processes at encoding (as measured with reading times). At the same time, we again found recognition performance to be unaffected by the amount of change. We discuss these findings in light of current event cognition theories. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

  12. The human right of access to drinking water: a continental analysis based on World Water Forums

    Directory of Open Access Journals (Sweden)

    Lorenzo Zorzi

    2016-11-01

    Full Text Available At the end of the 1980s, development and human rights were treated as separate issues, with distinct and divergent strategies and goals. After two decades, our understanding of the issue has evolved, and it has become clear that there is no way to separate the two issues. Currently, interest in human rights is increasing, and is focusing particularly on developing a consensus based upon international standards in order to promote and protect such rights. In this context, after numerous negotiations, the right to access potable water has come to be understood as a human right. This paper discusses the issue of water as a human right based upon the analysis of the World Water Forum which has existed since 1997 and involves the public, private and scientific sectors. The qualitative textual analysis was based upon documentation of these events.

  13. Analysis hierarchical model for discrete event systems

    Science.gov (United States)

    Ciortea, E. M.

    2015-11-01

    The This paper presents the hierarchical model based on discrete event network for robotic systems. Based on the hierarchical approach, Petri network is analysed as a network of the highest conceptual level and the lowest level of local control. For modelling and control of complex robotic systems using extended Petri nets. Such a system is structured, controlled and analysed in this paper by using Visual Object Net ++ package that is relatively simple and easy to use, and the results are shown as representations easy to interpret. The hierarchical structure of the robotic system is implemented on computers analysed using specialized programs. Implementation of hierarchical model discrete event systems, as a real-time operating system on a computer network connected via a serial bus is possible, where each computer is dedicated to local and Petri model of a subsystem global robotic system. Since Petri models are simplified to apply general computers, analysis, modelling, complex manufacturing systems control can be achieved using Petri nets. Discrete event systems is a pragmatic tool for modelling industrial systems. For system modelling using Petri nets because we have our system where discrete event. To highlight the auxiliary time Petri model using transport stream divided into hierarchical levels and sections are analysed successively. Proposed robotic system simulation using timed Petri, offers the opportunity to view the robotic time. Application of goods or robotic and transmission times obtained by measuring spot is obtained graphics showing the average time for transport activity, using the parameters sets of finished products. individually.

  14. The use of geoinformatic data and spatial analysis to predict faecal pollution during extreme precipitation events

    Science.gov (United States)

    Ward, Ray; Purnell, Sarah; Ebdon, James; Nnane, Daniel; Taylor, Huw

    2013-04-01

    be a major factor contributing to increased levels of FIO. This study identifies areas within the catchment that are likely to demonstrate elevated erosion rates during extreme precipitation events, which are likely to result in raised levels of FIO. The results also demonstrate that increases in the human faecal marker were associated with the discharge points of wastewater treatment works, and that levels of the marker increased whenever the works discharged untreated wastewaters during extreme precipitation. Spatial analysis also highlighted locations where human faecal pollution was present in areas away from wastewater treatment plants, highlighting the potential significance of inputs from septic tanks and other un-sewered domestic wastewater systems. Increases in the frequency of extreme precipitation events in many parts of Europe are likely to result in increased levels of water pollution from both point- and diffuse-sources, increasing the input of pathogens into surface waters, and elevating the health risks to downstream consumers of abstracted drinking water. This study suggests an approach that integrates water microbiology and geoinformatic data to support a 'prediction and prevention' approach, in place of the traditional focus on water quality monitoring. This work may therefore make a significant contribution to future European water resource management and health protection.

  15. Evaluation of 6 and 10 Year-Old Child Human Body Models in Emergency Events.

    Science.gov (United States)

    Gras, Laure-Lise; Stockman, Isabelle; Brolin, Karin

    2017-01-01

    Emergency events can influence a child's kinematics prior to a car-crash, and thus its interaction with the restraint system. Numerical Human Body Models (HBMs) can help understand the behaviour of children in emergency events. The kinematic responses of two child HBMs-MADYMO 6 and 10 year-old models-were evaluated and compared with child volunteers' data during emergency events-braking and steering-with a focus on the forehead and sternum displacements. The response of the 6 year-old HBM was similar to the response of the 10 year-old HBM, however both models had a different response compared with the volunteers. The forward and lateral displacements were within the range of volunteer data up to approximately 0.3 s; but then, the HBMs head and sternum moved significantly downwards, while the volunteers experienced smaller displacement and tended to come back to their initial posture. Therefore, these HBMs, originally intended for crash simulations, are not too stiff and could be able to reproduce properly emergency events thanks, for instance, to postural control.

  16. Evaluation of Fourier integral. Spectral analysis of seismic events

    International Nuclear Information System (INIS)

    Chitaru, Cristian; Enescu, Dumitru

    2003-01-01

    Spectral analysis of seismic events represents a method for great earthquake prediction. The seismic signal is not a sinusoidal signal; for this, it is necessary to find a method for best approximation of real signal with a sinusoidal signal. The 'Quanterra' broadband station allows the data access in numerical and/or graphical forms. With the numerical form we can easily make a computer program (MSOFFICE-EXCEL) for spectral analysis. (authors)

  17. The impact of MIS-3 climate events at the transition from Neanderthals to modern humans in Europe

    Science.gov (United States)

    Staubwasser, M.; Dragusin, V.; Assonov, S.; Ersek, V.; Hoffmann, D.; Veres, D.; Onac, B. P.

    2017-12-01

    We report on last glacial stable C and O isotope records from two U-Th dated speleothems from Romania. The southerly record (Ascunsa Cave, South Carpathians) from the Danube region matches the pacing and relative change in amplitude of the Greenland ice temperature record at 30-50 ka BP as well as the abundance of coastal winter sea ice in the Black Sea. The northerly record (Tausoare Cave, East Carpathians) in parts shares the pacing of events with the Greenland or the southern Romanian record, but best matches northern Black Sea summer season temperature change. Heinrich events do not stand out in either record, but the temperature amplitudes of Greenland stadials and Black Sea records are generally reproduced. Based on similarity with the Black Sea we interpret the combined two speleothem records in terms of seasonal temperature change in central Eastern Europe. A climatic influence on the transition from Neanderthals to modern humans has long been suspected. However, the diachronous and spatially complex archaeologic succession across the Middle-Upper Paleolithic (MUPL) in Europe ( 38 - 48 ka) is difficult to reconcile with the millennial-scale pacing of northern hemisphere paleoclimate. Two extreme cold events at 44.0-43.3 recorded and 40.7-39.8 ka in the speleothems bracket the dates of the first known appearance of modern humans - the Aurignacian complex - and the disappearance of Neanderthals from most of Europe. These cold events are coeval with Greenland Stadials GS-12 and GS-10. The speleothem records generally match the paleosol/loess succession from central Europe across the MUPL. The combined record suggests that permafrost advance may have made central Europe uninhabitable at least during winter. The combined paleoclimate and archaeologic records suggest that depopulation-repopulation cycles may have occurred during and after each cold event. Repopulation of central Europe geographically favored the modern human Aurignacians from SE Europe.

  18. Pressure Effects Analysis of National Ignition Facility Capacitor Module Events

    International Nuclear Information System (INIS)

    Brereton, S; Ma, C; Newton, M; Pastrnak, J; Price, D; Prokosch, D

    1999-01-01

    Capacitors and power conditioning systems required for the National Ignition Facility (NIF) have experienced several catastrophic failures during prototype demonstration. These events generally resulted in explosion, generating a dramatic fireball and energetic shrapnel, and thus may present a threat to the walls of the capacitor bay that houses the capacitor modules. The purpose of this paper is to evaluate the ability of the capacitor bay walls to withstand the overpressure generated by the aforementioned events. Two calculations are described in this paper. The first one was used to estimate the energy release during a fireball event and the second one was used to estimate the pressure in a capacitor module during a capacitor explosion event. Both results were then used to estimate the subsequent overpressure in the capacitor bay where these events occurred. The analysis showed that the expected capacitor bay overpressure was less than the pressure tolerance of the walls. To understand the risk of the above events in NIF, capacitor module failure probabilities were also calculated. This paper concludes with estimates of the probability of single module failure and multi-module failures based on the number of catastrophic failures in the prototype demonstration facility

  19. Regression analysis of mixed recurrent-event and panel-count data with additive rate models.

    Science.gov (United States)

    Zhu, Liang; Zhao, Hui; Sun, Jianguo; Leisenring, Wendy; Robison, Leslie L

    2015-03-01

    Event-history studies of recurrent events are often conducted in fields such as demography, epidemiology, medicine, and social sciences (Cook and Lawless, 2007, The Statistical Analysis of Recurrent Events. New York: Springer-Verlag; Zhao et al., 2011, Test 20, 1-42). For such analysis, two types of data have been extensively investigated: recurrent-event data and panel-count data. However, in practice, one may face a third type of data, mixed recurrent-event and panel-count data or mixed event-history data. Such data occur if some study subjects are monitored or observed continuously and thus provide recurrent-event data, while the others are observed only at discrete times and hence give only panel-count data. A more general situation is that each subject is observed continuously over certain time periods but only at discrete times over other time periods. There exists little literature on the analysis of such mixed data except that published by Zhu et al. (2013, Statistics in Medicine 32, 1954-1963). In this article, we consider the regression analysis of mixed data using the additive rate model and develop some estimating equation-based approaches to estimate the regression parameters of interest. Both finite sample and asymptotic properties of the resulting estimators are established, and the numerical studies suggest that the proposed methodology works well for practical situations. The approach is applied to a Childhood Cancer Survivor Study that motivated this study. © 2014, The International Biometric Society.

  20. The 2008 M7.9 Wenchuan earthquake - a human-caused event

    Science.gov (United States)

    Klose, C. D.

    2013-12-01

    A catalog of global human-caused earthquakes shows statistical evidence that the triggering of earthquakes by large-scale geoengineering activities depends on geological and tectonic constrains (in Klose 2013). Such geoengineering activities also include the filling of water reservoirs. This presentation illuminates mechanical and statistical aspects of the 2008 M7.9 Wenchuan earthquake in light of the hypothesis of being NOT human-caused. However, available data suggest that the Wenchuan earthquake was triggered by the filling of the Zipungpu water reservoir 30 months prior to the mainshock. The reservoir spatially extended parallel and near to the main Beichuan fault zone in a highly stressed reverse fault regime. It is mechanically evident that reverse faults tend to be very trigger-sensitive due to mass shifts (static loads) that occur on the surface of the Earth's crust. These circumstances made a triggering of a seismic event of this magnitude at this location possible (in Klose 2008, 2012). The data show that the Wenchuan earthquake is not an outlier. From a statistical view point, the earthquake falls into the upper range of the family of reverse fault earthquakes that were caused by humans worldwide.

  1. Urbanization and fertility: an event-history analysis of coastal Ghana.

    Science.gov (United States)

    White, Michael J; Muhidin, Salut; Andrzejewski, Catherine; Tagoe, Eva; Knight, Rodney; Reed, Holly

    2008-11-01

    In this article, we undertake an event-history analysis of fertility in Ghana. We exploit detailed life history calendar data to conduct a more refined and definitive analysis of the relationship among personal traits, urban residence, and fertility. Although urbanization is generally associated with lower fertility in developing countries, inferences in most studies have been hampered by a lack of information about the timing of residence in relationship to childbearing. We find that the effect of urbanization itself is strong, evident, and complex, and persists after we control for the effects of age, cohort, union status, and education. Our discrete-time event-history analysis shows that urban women exhibit fertility rates that are, on average, 11% lower than those of rural women, but the effects vary by parity. Differences in urban population traits would augment the effects of urban adaptation itself Extensions of the analysis point to the operation of a selection effect in rural-to-urban mobility but provide limited evidence for disruption effects. The possibility of further selection of urbanward migrants on unmeasured traits remains. The analysis also demonstrates the utility of an annual life history calendar for collecting such data in the field.

  2. Human reliability assessment on the basis of operating experience

    International Nuclear Information System (INIS)

    Straeter, O.

    1997-01-01

    For development of methodology, available models for qualitative assessment of human errors (e.g. by Swain, Hacker, Rasmussen) and a variety of known systematic approaches for quantitiative assessment of inadequate human action (e.g. THERP, ASEP, HCR, SLIM) were taken as a basis to establish a job specification, which in turn was used for developing a method for acquisition, characterisation and evaluation of errors. This method encompasses the two processes of event analysis and event evaluation: The first step comprises analysis of events by analysis of information describing the conditions and scenarios of relevance to the inadequate human action examined. In addition to the description of process sequences, information is taken into account on possible conditions that may bring about failure. As an assessment of human reliability requires manifold approaches for evaluation, a connectionistic procedure was developed for evaluation of the compilation of events based on a debate about various approaches from the domain of artificial intelligence (AI). This procedure yields both qualitative and quantitative information through a homogenous approach. (orig./GL) [de

  3. Contributions of human activities to suspended-sediment yield during storm events from a steep, small, tropical watershed, American Samoa

    Science.gov (United States)

    Messina, A. T.; Biggs, T. W.

    2014-12-01

    Anthropogenic watershed disturbance by agriculture, deforestation, roads, and urbanization can alter the timing, composition, and mass of sediment loads to adjacent coral reefs, causing enhanced sediment stress on corals near the outlets of impacted watersheds like Faga'alu, American Samoa. To quantify the increase in sediment loading to the adjacent priority coral reef experiencing sedimentation stress, suspended-sediment yield (SSY) from undisturbed and human-disturbed portions of a small, steep, tropical watershed was measured during baseflow and storm events of varying magnitude. Data on precipitation, discharge, turbidity, and suspended-sediment concentration (SSC) were collected over three field campaigns and continuous monitoring from January 2012 to March 2014, which included 88 storm events. A combination of paired- and nested-watershed study designs using sediment budget, disturbance ratio, and sediment rating curve methodologies was used to quantify the contribution of human-disturbed areas to total SSY. SSC during base- and stormflows was significantly higher downstream of an open-pit aggregate quarry, indicating the quarry is a key sediment source requiring sediment discharge mitigation. Comparison of event-wise SSY from the upper, undisturbed watershed, and the lower, human-disturbed watershed showed the Lower watershed accounted for more than 80% of total SSY on average, and human activities have increased total sediment loading to the coast by approximately 200%. Four storm characteristics were tested as predictors of event SSY using Pearson's and Spearman's correlation coefficients. Similar to mountainous watersheds in semi-arid and temperate watersheds, SSY from both the undisturbed and disturbed watersheds had the highest correlation with event maximum discharge, Qmax (Pearson's R=0.88 and 0.86 respectively), and were best fit by a power law relationship. The resulting model of event-SSY from Faga'alu is being incorporated as part of a larger

  4. Automatically ordering events and times in text

    CERN Document Server

    Derczynski, Leon R A

    2017-01-01

    The book offers a detailed guide to temporal ordering, exploring open problems in the field and providing solutions and extensive analysis. It addresses the challenge of automatically ordering events and times in text. Aided by TimeML, it also describes and presents concepts relating to time in easy-to-compute terms. Working out the order that events and times happen has proven difficult for computers, since the language used to discuss time can be vague and complex. Mapping out these concepts for a computational system, which does not have its own inherent idea of time, is, unsurprisingly, tough. Solving this problem enables powerful systems that can plan, reason about events, and construct stories of their own accord, as well as understand the complex narratives that humans express and comprehend so naturally. This book presents a theory and data-driven analysis of temporal ordering, leading to the identification of exactly what is difficult about the task. It then proposes and evaluates machine-learning so...

  5. Simulating the physiology of athletes during endurance sports events: modelling human energy conversion and metabolism

    NARCIS (Netherlands)

    van Beek, J.H.G.M.; Supandi, F.B.; Gavai, Anand; de Graaf, A.A.; Binsl, T.W.; Hettling, H.

    2011-01-01

    The human physiological system is stressed to its limits during endurance sports competition events.We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We

  6. Simulating the physiology of athletes during endurance sports events: Modelling human energy conversion and metabolism

    NARCIS (Netherlands)

    Beek, J.H.G.M. van; Supandi, F.; Gavai, A.K.; Graaf, A.A. de; Binsl, T.W.; Hettling, H.

    2011-01-01

    The human physiological system is stressed to its limits during endurance sports competition events.We describe a whole body computational model for energy conversion during bicycle racing. About 23 per cent of the metabolic energy is used for muscle work, the rest is converted to heat. We

  7. The human impact of volcanoes: a historical review of events 1900-2009 and systematic literature review.

    Science.gov (United States)

    Doocy, Shannon; Daniels, Amy; Dooling, Shayna; Gorokhovich, Yuri

    2013-04-16

    Introduction. More than 500 million people live within the potential exposure range of a volcano. The risk of catastrophic losses in future eruptions is significant given population growth, proximities of major cities to volcanoes, and the possibility of larger eruptions. The objectives of this review are to describe the impact of volcanoes on the human population, in terms of mortality, injury, and displacement and, to the extent possible, identify risk factors associated with these outcomes. This is one of five reviews on the human impact of natural disasters. Methods. Data on the impact of volcanoes were compiled using two methods, a historical review of volcano events from 1900 to 2009 from multiple databases and a systematic literature review of publications ending in October 2012. Analysis included descriptive statistics and bivariate tests for associations between volcano mortality and characteristics using STATA 11. Findings. There were a total of 91,789 deaths (range: 81,703-102,372), 14,068 injuries (range 11,541-17,922), and 4.72 million people affected by volcanic events between 1900 and 2008. Inconsistent reporting suggests this is an underestimate, particularly in terms of numbers injured and affected. The primary causes of mortality in recent volcanic eruptions were ash asphyxiation, thermal injuries from pyroclastic flow, and trauma. Mortality was concentrated with the ten deadliest eruptions accounting for more than 80% of deaths; 84% of fatalities occurred in four locations (the Island of Martinique (France), Colombia, Indonesia, and Guatemala). Conclusions. Changes in land use practices and population growth provide a background for increasing risk; in conjunction with increasing urbanization in at risk areas, this poses a challenge for future volcano preparedness and mitigation efforts.

  8. Extreme weather events and infectious disease outbreaks.

    Science.gov (United States)

    McMichael, Anthony J

    2015-01-01

    Human-driven climatic changes will fundamentally influence patterns of human health, including infectious disease clusters and epidemics following extreme weather events. Extreme weather events are projected to increase further with the advance of human-driven climate change. Both recent and historical experiences indicate that infectious disease outbreaks very often follow extreme weather events, as microbes, vectors and reservoir animal hosts exploit the disrupted social and environmental conditions of extreme weather events. This review article examines infectious disease risks associated with extreme weather events; it draws on recent experiences including Hurricane Katrina in 2005 and the 2010 Pakistan mega-floods, and historical examples from previous centuries of epidemics and 'pestilence' associated with extreme weather disasters and climatic changes. A fuller understanding of climatic change, the precursors and triggers of extreme weather events and health consequences is needed in order to anticipate and respond to the infectious disease risks associated with human-driven climate change. Post-event risks to human health can be constrained, nonetheless, by reducing background rates of persistent infection, preparatory action such as coordinated disease surveillance and vaccination coverage, and strengthened disaster response. In the face of changing climate and weather conditions, it is critically important to think in ecological terms about the determinants of health, disease and death in human populations.

  9. Study of the peculiarities of multiparticle production via event-by-event analysis in asymmetric nucleus-nucleus interactions

    Science.gov (United States)

    Fedosimova, Anastasiya; Gaitinov, Adigam; Grushevskaya, Ekaterina; Lebedev, Igor

    2017-06-01

    In this work the study on the peculiarities of multiparticle production in interactions of asymmetric nuclei to search for unusual features of such interactions, is performed. A research of long-range and short-range multiparticle correlations in the pseudorapidity distribution of secondary particles on the basis of analysis of individual interactions of nuclei of 197 Au at energy 10.7 AGeV with photoemulsion nuclei, is carried out. Events with long-range multiparticle correlations (LC), short-range multiparticle correlations (SC) and mixed type (MT) in pseudorapidity distribution of secondary particles, are selected by the Hurst method in accordance with Hurst curve behavior. These types have significantly different characteristics. At first, they have different fragmentation parameters. Events of LC type are processes of full destruction of the projectile nucleus, in which multicharge fragments are absent. In events of mixed type several multicharge fragments of projectile nucleus are discovered. Secondly, these two types have significantly different multiplicity distribution. The mean multiplicity of LC type events is significantly more than in mixed type events. On the basis of research of the dependence of multiplicity versus target-nuclei fragments number for events of various types it is revealed, that the most considerable multiparticle correlations are observed in interactions of the mixed type, which correspond to the central collisions of gold nuclei and nuclei of CNO-group, i.e. nuclei with strongly asymmetric volume, nuclear mass, charge, etc. Such events are characterised by full destruction of the target-nucleus and the disintegration of the projectile-nucleus on several multi-charged fragments.

  10. Study of the peculiarities of multiparticle production via event-by-event analysis in asymmetric nucleus-nucleus interactions

    Directory of Open Access Journals (Sweden)

    Fedosimova Anastasiya

    2017-01-01

    Full Text Available In this work the study on the peculiarities of multiparticle production in interactions of asymmetric nuclei to search for unusual features of such interactions, is performed. A research of long-range and short-range multiparticle correlations in the pseudorapidity distribution of secondary particles on the basis of analysis of individual interactions of nuclei of 197 Au at energy 10.7 AGeV with photoemulsion nuclei, is carried out. Events with long-range multiparticle correlations (LC, short-range multiparticle correlations (SC and mixed type (MT in pseudorapidity distribution of secondary particles, are selected by the Hurst method in accordance with Hurst curve behavior. These types have significantly different characteristics. At first, they have different fragmentation parameters. Events of LC type are processes of full destruction of the projectile nucleus, in which multicharge fragments are absent. In events of mixed type several multicharge fragments of projectile nucleus are discovered. Secondly, these two types have significantly different multiplicity distribution. The mean multiplicity of LC type events is significantly more than in mixed type events. On the basis of research of the dependence of multiplicity versus target-nuclei fragments number for events of various types it is revealed, that the most considerable multiparticle correlations are observed in interactions of the mixed type, which correspond to the central collisions of gold nuclei and nuclei of CNO-group, i.e. nuclei with strongly asymmetric volume, nuclear mass, charge, etc. Such events are characterised by full destruction of the target-nucleus and the disintegration of the projectile-nucleus on several multi-charged fragments.

  11. Recurring Events in the Finnish Nuclear Power Plants

    International Nuclear Information System (INIS)

    Suksi, Seija; Olander, Ronnie; Tiippana, Petteri

    2003-01-01

    An analysis and evaluation of event investigation methods applied by the Radiation and Nuclear Safety Authority (STUK), and the two Finnish nuclear power plant operators Teollisuuden Voima Oy (TVO) and Fortum Power and Heat Oy (Fortum) was carried out by the Technical Research Centre (VIT) on an assignment from STUK. The study aimed at providing a broad overview of the whole organisational framework to support event investigation practices at the regulatory body and at the utilities. The study was part of the IAEA Co-ordinated Research Programme (CRP) on 'Investigation of Methodologies for Incident Analysis'. The main objective of the research was to evaluate the adequacy and reliability of event investigation analysis methods and practices in the Finnish nuclear power industry and based on the results to further develop them. In general, the direct causes of identified events could be detected and eliminated, but more emphasis should be given to the prevention of recurrence of events and identification of common causes and latent failures. The study showed that the evaluated organisations had rather comprehensive incident analysis arrangements. The study also showed that more focus and prioritisation are needed. Deficiencies were identified mostly in the areas of recording, assessment and classification of new events, use of existing operating experience data, utilisation of information technology tools, and allocation of work and resources. Also the indicators or measures for the effectiveness of event investigation and operating experience feedback were missing. All organisations should maintain adequate resources in this area. The researchers suggested a more effective operating experience feedback loop. Especially more attention should be paid to root cause analysis of significant events, tasks and activities where the initial errors have occurred, and weaknesses of defensive barriers. It was also recommended that implementing periodic operational experience

  12. The development of human behaviour analysis techniques -The development of human factors technologies-

    International Nuclear Information System (INIS)

    Lee, Jung Woon; Cheon, Se Woo; Shu, Sang Moon; Park, Geun Ok; Lee, Yong Hee; Lee, Han Yeong; Park, Jae Chang; Lee, Eu Jin; Lee, Seung Hee

    1994-04-01

    This project has two major areas ; one is the development of an operator task simulation software and another is the development of human error analysis and application technologies. In this year project, the second year, for the development of an operator task simulation software, we studied the followings: - analysis of the characteristics of operator tasks, - development of operator task structures : Macro Structures, - development of an operator task simulation analyzes, - analysis of performance measures. And the followings for the development of human error analysis and application technologies : - analysis of human error mechanisms, - analysis of human error characteristics in tasks, - analysis of human error occurrence in Korean Nuclear Power Plants, - establishment of an experimental environment for human error data collection with Compact Nuclear Simulator, - basic design of a Multimedia-based Human Error Representing System. (Author)

  13. Idaho National Laboratory Quarterly Event Performance Analysis FY 2013 4th Quarter

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Lisbeth A. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2013-11-01

    This report is published quarterly by the Idaho National Laboratory (INL) Performance Assurance Organization. The Department of Energy Occurrence Reporting and Processing System (ORPS) as prescribed in DOE Order 232.2 “Occurrence Reporting and Processing of Operations Information” requires a quarterly analysis of events, both reportable and not reportable for the previous twelve months. This report is the analysis of occurrence reports and deficiency reports (including not reportable events) identified at the Idaho National Laboratory (INL) during the period of October 2012 through September 2013.

  14. User`s manual of a support system for human reliability analysis

    Energy Technology Data Exchange (ETDEWEB)

    Yokobayashi, Masao [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Tamura, Kazuo

    1995-10-01

    Many kinds of human reliability analysis (HRA) methods have been developed. However, users are required to be skillful so as to use them, and also required complicated works such as drawing event tree (ET) and calculation of uncertainty bounds. Moreover, each method is not so complete that only one method of them is not enough to evaluate human reliability. Therefore, a personal computer (PC) based support system for HRA has been developed to execute HRA practically and efficiently. The system consists of two methods, namely, simple method and detailed one. The former uses ASEP that is a simplified THERP-technique, and combined method of OAT and HRA-ET/DeBDA is used for the latter. Users can select a suitable method for their purpose. Human error probability (HEP) data were collected and a database of them was built to use for the support system. This paper describes outline of the HRA methods, support functions and user`s guide of the system. (author).

  15. Normalization Strategies for Enhancing Spatio-Temporal Analysis of Social Media Responses during Extreme Events: A Case Study based on Analysis of Four Extreme Events using Socio-Environmental Data Explorer (SEDE

    Directory of Open Access Journals (Sweden)

    J. Ajayakumar

    2017-10-01

    Full Text Available With social media becoming increasingly location-based, there has been a greater push from researchers across various domains including social science, public health, and disaster management, to tap in the spatial, temporal, and textual data available from these sources to analyze public response during extreme events such as an epidemic outbreak or a natural disaster. Studies based on demographics and other socio-economic factors suggests that social media data could be highly skewed based on the variations of population density with respect to place. To capture the spatio-temporal variations in public response during extreme events we have developed the Socio-Environmental Data Explorer (SEDE. SEDE collects and integrates social media, news and environmental data to support exploration and assessment of public response to extreme events. For this study, using SEDE, we conduct spatio-temporal social media response analysis on four major extreme events in the United States including the “North American storm complex” in December 2015, the “snowstorm Jonas” in January 2016, the “West Virginia floods” in June 2016, and the “Hurricane Matthew” in October 2016. Analysis is conducted on geo-tagged social media data from Twitter and warnings from the storm events database provided by National Centers For Environmental Information (NCEI for analysis. Results demonstrate that, to support complex social media analyses, spatial and population-based normalization and filtering is necessary. The implications of these results suggests that, while developing software solutions to support analysis of non-conventional data sources such as social media, it is quintessential to identify the inherent biases associated with the data sources, and adapt techniques and enhance capabilities to mitigate the bias. The normalization strategies that we have developed and incorporated to SEDE will be helpful in reducing the population bias associated with

  16. Normalization Strategies for Enhancing Spatio-Temporal Analysis of Social Media Responses during Extreme Events: A Case Study based on Analysis of Four Extreme Events using Socio-Environmental Data Explorer (SEDE)

    Science.gov (United States)

    Ajayakumar, J.; Shook, E.; Turner, V. K.

    2017-10-01

    With social media becoming increasingly location-based, there has been a greater push from researchers across various domains including social science, public health, and disaster management, to tap in the spatial, temporal, and textual data available from these sources to analyze public response during extreme events such as an epidemic outbreak or a natural disaster. Studies based on demographics and other socio-economic factors suggests that social media data could be highly skewed based on the variations of population density with respect to place. To capture the spatio-temporal variations in public response during extreme events we have developed the Socio-Environmental Data Explorer (SEDE). SEDE collects and integrates social media, news and environmental data to support exploration and assessment of public response to extreme events. For this study, using SEDE, we conduct spatio-temporal social media response analysis on four major extreme events in the United States including the "North American storm complex" in December 2015, the "snowstorm Jonas" in January 2016, the "West Virginia floods" in June 2016, and the "Hurricane Matthew" in October 2016. Analysis is conducted on geo-tagged social media data from Twitter and warnings from the storm events database provided by National Centers For Environmental Information (NCEI) for analysis. Results demonstrate that, to support complex social media analyses, spatial and population-based normalization and filtering is necessary. The implications of these results suggests that, while developing software solutions to support analysis of non-conventional data sources such as social media, it is quintessential to identify the inherent biases associated with the data sources, and adapt techniques and enhance capabilities to mitigate the bias. The normalization strategies that we have developed and incorporated to SEDE will be helpful in reducing the population bias associated with social media data and will be useful

  17. Human Performance Evaluation System

    International Nuclear Information System (INIS)

    Hardwick, R.J. Jr.

    1985-01-01

    Operating nuclear power plants requires high standards of performance, extensive training and responsive management. Despite our best efforts inappropriate human actions do occur, but they can be managed. An extensive review of License Event Reports (LERs) was conducted which indicated continual inadequacy in human performance and in evaluation of root causes. Of some 31,000 LERs, about 5,000 or 16% were directly attributable to inappropriate actions. A recent analysis of 87 Significant Event Reports (issued by INPO in 1983) identified inappropriate actions as being the most frequent root cause (44% of the total). A more recent analysis of SERs issued in 1983 and 1984 indicate that 52% of the root causes were attributed to human performance. The Human Performance Evaluation System (HPES) is a comprehensive, coordinated utility/industry system for evaluating and reporting human performance situtations. HPES is a result of the realization that current reporting system provide limited treatment of human performance and rarely provide adequate information about root causes of inappropriate actions by individuals. The HPES was implemented to identify and eliminate root causes of inappropriate actions

  18. Thermodynamical analysis of human thermal comfort

    International Nuclear Information System (INIS)

    Prek, Matjaz

    2006-01-01

    Traditional methods of human thermal comfort analysis are based on the first law of thermodynamics. These methods use an energy balance of the human body to determine heat transfer between the body and its environment. By contrast, the second law of thermodynamics introduces the useful concept of exergy. It enables the determination of the exergy consumption within the human body dependent on human and environmental factors. Human body exergy consumption varies with the combination of environmental (room) conditions. This process is related to human thermal comfort in connection with temperature, heat, and mass transfer. In this paper a thermodynamic analysis of human heat and mass transfer based on the 2nd law of thermodynamics in presented. It is shown that the human body's exergy consumption in relation to selected human parameters exhibits a minimal value at certain combinations of environmental parameters. The expected thermal sensation also shows that there is a correlation between exergy consumption and thermal sensation. Thus, our analysis represents an improvement in human thermal modelling and gives more information about the environmental impact on expected human thermal sensation

  19. Disruptive Event Biosphere Dose Conversion Factor Analysis

    Energy Technology Data Exchange (ETDEWEB)

    M. A. Wasiolek

    2003-07-21

    This analysis report, ''Disruptive Event Biosphere Dose Conversion Factor Analysis'', is one of the technical reports containing documentation of the ERMYN (Environmental Radiation Model for Yucca Mountain Nevada) biosphere model for the geologic repository at Yucca Mountain, its input parameters, and the application of the model to perform the dose assessment for the repository. The biosphere model is one of a series of process models supporting the Total System Performance Assessment (TSPA) for the Yucca Mountain repository. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of the two reports that develop biosphere dose conversion factors (BDCFs), which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2003 [DIRS 164186]) describes in detail the conceptual model as well as the mathematical model and lists its input parameters. Model input parameters are developed and described in detail in five analysis report (BSC 2003 [DIRS 160964], BSC 2003 [DIRS 160965], BSC 2003 [DIRS 160976], BSC 2003 [DIRS 161239], and BSC 2003 [DIRS 161241]). The objective of this analysis was to develop the BDCFs for the volcanic ash exposure scenario and the dose factors (DFs) for calculating inhalation doses during volcanic eruption (eruption phase of the volcanic event). The volcanic ash exposure scenario is hereafter referred to as the volcanic ash scenario. For the volcanic ash scenario, the mode of radionuclide release into the biosphere is a volcanic eruption through the repository with the resulting entrainment of contaminated waste in the tephra and the subsequent atmospheric transport and dispersion of contaminated material in

  20. Disruptive Event Biosphere Dose Conversion Factor Analysis

    International Nuclear Information System (INIS)

    M. A. Wasiolek

    2003-01-01

    This analysis report, ''Disruptive Event Biosphere Dose Conversion Factor Analysis'', is one of the technical reports containing documentation of the ERMYN (Environmental Radiation Model for Yucca Mountain Nevada) biosphere model for the geologic repository at Yucca Mountain, its input parameters, and the application of the model to perform the dose assessment for the repository. The biosphere model is one of a series of process models supporting the Total System Performance Assessment (TSPA) for the Yucca Mountain repository. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of the two reports that develop biosphere dose conversion factors (BDCFs), which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2003 [DIRS 164186]) describes in detail the conceptual model as well as the mathematical model and lists its input parameters. Model input parameters are developed and described in detail in five analysis report (BSC 2003 [DIRS 160964], BSC 2003 [DIRS 160965], BSC 2003 [DIRS 160976], BSC 2003 [DIRS 161239], and BSC 2003 [DIRS 161241]). The objective of this analysis was to develop the BDCFs for the volcanic ash exposure scenario and the dose factors (DFs) for calculating inhalation doses during volcanic eruption (eruption phase of the volcanic event). The volcanic ash exposure scenario is hereafter referred to as the volcanic ash scenario. For the volcanic ash scenario, the mode of radionuclide release into the biosphere is a volcanic eruption through the repository with the resulting entrainment of contaminated waste in the tephra and the subsequent atmospheric transport and dispersion of contaminated material in the biosphere. The biosphere process

  1. Internal event analysis of Laguna Verde Unit 1 Nuclear Power Plant. System Analysis; Analisis de Eventos Internos para la Unidad 1 de la Central Nucleoelectrica de Laguna Verde. Analisis de sistemas

    Energy Technology Data Exchange (ETDEWEB)

    Huerta B, A; Aguilar T, O; Nunez C, A; Lopez M, R [Comision Nacional de Seguridad Nuclear y Salvaguardias, 03000 Mexico D.F. (Mexico)

    1993-07-01

    The Level 1 results of Laguna Verde Nuclear Power Plant PRA are presented in the {sup I}nternal Event Analysis of Laguna Verde Unit 1 Nuclear Power Plant{sup ,} CNSNS-TR-004, in five volumes. The reports are organized as follows: CNSNS-TR-004 Volume 1: Introduction and Methodology. CNSNS-TR-004 Volume 2: Initiating Event and Accident Sequences. CNSNS-TR-004 Volume 3: System Analysis. CNSNS-TR-004 Volume 4: Accident Sequence Quantification and Results. CNSNS-TR-004 Volume 5: Appendices A, B and C. This volume presents the results of the system analysis for the Laguna Verde Unit 1 Nuclear Power Plant. The system analysis involved the development of logical models for all the systems included in the accident sequence event tree headings, and for all the support systems required to operate the front line systems. For the Internal Event analysis for Laguna Verde, 16 front line systems and 5 support systems were included. Detailed fault trees were developed for most of the important systems. Simplified fault trees focusing on major faults were constructed for those systems that can be adequately represent,ed using this kind of modeling. For those systems where fault tree models were not constructed, actual data were used to represent the dominant failures of the systems. The main failures included in the fault trees are hardware failures, test and maintenance unavailabilities, common cause failures, and human errors. The SETS and TEMAC codes were used to perform the qualitative and quantitative fault tree analyses. (Author)

  2. Human Bacteroides and total coliforms as indicators of recent combined sewer overflows and rain events in urban creeks.

    Science.gov (United States)

    McGinnis, Shannon; Spencer, Susan; Firnstahl, Aaron; Stokdyk, Joel; Borchardt, Mark; McCarthy, David T; Murphy, Heather M

    2018-07-15

    Combined sewer overflows (CSOs) are a known source of human fecal pollution and human pathogens in urban water bodies, which may present a significant public health threat. To monitor human fecal contamination in water, bacterial fecal indicator organisms (FIOs) are traditionally used. However, because FIOs are not specific to human sources and do not correlate with human pathogens, alternative fecal indicators detected using qPCR are becoming of interest to policymakers. For this reason, this study measured correlations between the number and duration of CSOs and mm of rainfall, concentrations of traditional FIOs and alternative indicators, and the presence of human pathogens in two urban creeks. Samples were collected May-July 2016 and analyzed for concentrations of FIOs (total coliforms and E. coli) using membrane filtration as well as for three alternative fecal indicators (human Bacteroides HF183 marker, human polyomavirus (HPoV), pepper mild mottle virus (PMMoV)) and nine human pathogens using qPCR. Four of the nine pathogens analyzed were detected at these sites including adenovirus, Enterohemorrhagic E. coli, norovirus, and Salmonella. Among all indicators studied, human Bacteroides and total coliforms were significantly correlated with recent CSO and rainfall events, while E. coli, PMMoV, and HPoV did not show consistent significant correlations. Further, human Bacteroides were a more specific indicator, while total coliforms were a more sensitive indicator of CSO and rainfall events. Results may have implications for the use and interpretation of these indicators in future policy or monitoring programs. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Human Bacteroides and total coliforms as indicators of recent combined sewer overflows and rain events in urban creeks

    Science.gov (United States)

    McGinnis, Shannon; Spencer, Susan K.; Firnstahl, Aaron; Stokdyk, Joel; Borchardt, Mark A.; McCarthy, David; Murphy, Heather

    2018-01-01

    Combined sewer overflows (CSOs) are a known source of human fecal pollution and human pathogens in urban water bodies, which may present a significant public health threat. To monitor human fecal contamination in water, bacterial fecal indicator organisms (FIOs) are traditionally used. However, because FIOs are not specific to human sources and do not correlate with human pathogens, alternative fecal indicators detected using qPCR are becoming of interest to policymakers. For this reason, this study measured correlations between the number and duration of CSOs and mm of rainfall, concentrations of traditional FIOs and alternative indicators, and the presence of human pathogens in two urban creeks. Samples were collected May–July 2016 and analyzed for concentrations of FIOs (total coliforms and E. coli) using membrane filtration as well as for three alternative fecal indicators (human Bacteroides HF183 marker, human polyomavirus (HPoV), pepper mild mottle virus (PMMoV)) and nine human pathogens using qPCR. Four of the nine pathogens analyzed were detected at these sites including adenovirus, Enterohemorrhagic E. coli, norovirus, and Salmonella. Among all indicators studied, human Bacteroides and total coliforms were significantly correlated with recent CSO and rainfall events, while E. coli, PMMoV, and HPoV did not show consistent significant correlations. Further, human Bacteroides were a more specific indicator, while total coliforms were a more sensitive indicator of CSO and rainfall events. Results may have implications for the use and interpretation of these indicators in future policy or monitoring programs.

  4. 'It was a freak accident': an analysis of the labelling of injury events in the US press.

    Science.gov (United States)

    Smith, Katherine C; Girasek, Deborah C; Baker, Susan P; Manganello, Jennifer A; Bowman, Stephen M; Samuels, Alicia; Gielen, Andrea C

    2012-02-01

    Given that the news media shape our understanding of health issues, a study was undertaken to examine the use by the US media of the expression 'freak accident' in relation to injury events. This analysis is intended to contribute to the ongoing consideration of lay conceptualisation of injuries as 'accidents'. LexisNexis Academic was used to search three purposively selected US news sources (Associated Press, New York Times and Philadelphia Inquirer) for the expression 'freak accident' over 5 years (2005-9). Textual analysis included both structured and open coding. Coding included measures for who used the expression within the story, the nature of the injury event and the injured person(s) being reported upon, incorporation of prevention information within the story and finally a phenomenological consideration of the uses and meanings of the expression within the story context. Results The search yielded a dataset of 250 human injury stories incorporating the term 'freak accident'. Injuries sustained by professional athletes dominated coverage (61%). Fewer than 10% of stories provided a clear and explicit injury prevention message. Stories in which journalists employed the expression 'freak accident' were less likely to include prevention information than stories in which the expression was used by people quoted in the story. Journalists who frame injury events as freak accidents may be an appropriate focus for advocacy efforts. Effective prevention messages should be developed and disseminated to accompany injury reporting in order to educate and protect the public.

  5. Identification of fire modeling issues based on an analysis of real events from the OECD FIRE database

    Energy Technology Data Exchange (ETDEWEB)

    Hermann, Dominik [Swiss Federal Nuclear Safety Inspectorate ENSI, Brugg (Switzerland)

    2017-03-15

    Precursor analysis is widely used in the nuclear industry to judge the significance of events relevant to safety. However, in case of events that may damage equipment through effects that are not ordinary functional dependencies, the analysis may not always fully appreciate the potential for further evolution of the event. For fires, which are one class of such events, this paper discusses modelling challenges that need to be overcome when performing a probabilistic precursor analysis. The events used to analyze are selected from the Organisation for Economic Cooperation and Development (OECD) Fire Incidents Records Exchange (FIRE) Database.

  6. Hazard analysis of typhoon-related external events using extreme value theory

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yo Chan; Jang, Seung Cheol [Integrated Safety Assessment Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of); Lim, Tae Jin [Dept. of Industrial Information Systems Engineering, Soongsil University, Seoul (Korea, Republic of)

    2015-02-15

    After the Fukushima accident, the importance of hazard analysis for extreme external events was raised. To analyze typhoon-induced hazards, which are one of the significant disasters of East Asian countries, a statistical analysis using the extreme value theory, which is a method for estimating the annual exceedance frequency of a rare event, was conducted for an estimation of the occurrence intervals or hazard levels. For the four meteorological variables, maximum wind speed, instantaneous wind speed, hourly precipitation, and daily precipitation, the parameters of the predictive extreme value theory models were estimated. The 100-year return levels for each variable were predicted using the developed models and compared with previously reported values. It was also found that there exist significant long-term climate changes of wind speed and precipitation. A fragility analysis should be conducted to ensure the safety levels of a nuclear power plant for high levels of wind speed and precipitation, which exceed the results of a previous analysis.

  7. Antipsychotics, glycemic disorders, and life-threatening diabetic events: a Bayesian data-mining analysis of the FDA adverse event reporting system (1968-2004).

    Science.gov (United States)

    DuMouchel, William; Fram, David; Yang, Xionghu; Mahmoud, Ramy A; Grogg, Amy L; Engelhart, Luella; Ramaswamy, Krishnan

    2008-01-01

    This analysis compared diabetes-related adverse events associated with use of different antipsychotic agents. A disproportionality analysis of the US Food and Drug Administration (FDA) Adverse Event Reporting System (AERS) was performed. Data from the FDA postmarketing AERS database (1968 through first quarter 2004) were evaluated. Drugs studied included aripiprazole, clozapine, haloperidol, olanzapine, quetiapine, risperidone, and ziprasidone. Fourteen Medical Dictionary for Regulatory Activities (MedDRA) Primary Terms (MPTs) were chosen to identify diabetes-related adverse events; 3 groupings into higher-level descriptive categories were also studied. Three methods of measuring drug-event associations were used: proportional reporting ratio, the empirical Bayes data-mining algorithm known as the Multi-Item Gamma Poisson Shrinker, and logistic regression (LR) analysis. Quantitative measures of association strength, with corresponding confidence intervals, between drugs and specified adverse events were computed and graphed. Some of the LR analyses were repeated separately for reports from patients under and over 45 years of age. Differences in association strength were declared statistically significant if the corresponding 90% confidence intervals did not overlap. Association with various glycemic events differed for different drugs. On average, the rankings of association strength agreed with the following ordering: low association, ziprasidone, aripiprazole, haloperidol, and risperidone; medium association, quetiapine; and strong association, clozapine and olanzapine. The median rank correlation between the above ordering and the 17 sets of LR coefficients (1 set for each glycemic event) was 93%. Many of the disproportionality measures were significantly different across drugs, and ratios of disproportionality factors of 5 or more were frequently observed. There are consistent and substantial differences between atypical antipsychotic drugs in the

  8. Magnesium and the Risk of Cardiovascular Events: A Meta-Analysis of Prospective Cohort Studies

    Science.gov (United States)

    Hao, Yongqiang; Li, Huiwu; Tang, Tingting; Wang, Hao; Yan, Weili; Dai, Kerong

    2013-01-01

    Background Prospective studies that have examined the association between dietary magnesium intake and serum magnesium concentrations and the risk of cardiovascular disease (CVD) events have reported conflicting findings. We undertook a meta-analysis to evaluate the association between dietary magnesium intake and serum magnesium concentrations and the risk of total CVD events. Methodology/Principal Findings We performed systematic searches on MEDLINE, EMBASE, and OVID up to February 1, 2012 without limits. Categorical, linear, and nonlinear, dose-response, heterogeneity, publication bias, subgroup, and meta-regression analysis were performed. The analysis included 532,979 participants from 19 studies (11 studies on dietary magnesium intake, 6 studies on serum magnesium concentrations, and 2 studies on both) with 19,926 CVD events. The pooled relative risks of total CVD events for the highest vs. lowest category of dietary magnesium intake and serum magnesium concentrations were 0.85 (95% confidence interval 0.78 to 0.92) and 0.77 (0.66 to 0.87), respectively. In linear dose-response analysis, only serum magnesium concentrations ranging from 1.44 to 1.8 mEq/L were significantly associated with total CVD events risk (0.91, 0.85 to 0.97) per 0.1 mEq/L (Pnonlinearity = 0.465). However, significant inverse associations emerged in nonlinear models for dietary magnesium intake (Pnonlinearity = 0.024). The greatest risk reduction occurred when intake increased from 150 to 400 mg/d. There was no evidence of publication bias. Conclusions/Significance There is a statistically significant nonlinear inverse association between dietary magnesium intake and total CVD events risk. Serum magnesium concentrations are linearly and inversely associated with the risk of total CVD events. PMID:23520480

  9. Human factors assessment in PRA using Task Analysis Linked Evaluation Technique (TALENT)

    International Nuclear Information System (INIS)

    Wells, J.E.; Banks, W.W.

    1991-01-01

    Thirty years ago the US military and US aviation industry, and more recently, in response to the US Three Mile Island and USSR Chernobyl accidents, the US commercial nuclear power industry, acknowledged that human error, as an immediate precursor, and as a latent or indirect influence in the form of training, maintainability, inservice test, and surveillance programs, is a primary contributor to unreality and risk in complex high-reliability systems. A 1985 Nuclear Regulatory Commission (NRC) study of Licensee Event Reports (LERs) suggests that upwards of 65% of commercial nuclear system failures involve human error. Despite the magnitude and nature of human error cited in that study, there has been limited attention to personnel-centered issues, especially person-to-person issues involving group processes, management and organizational environment. The paper discusses NRC integration and applications research with respect to the Task Analysis Linked Evaluation Technique (TALENT) in risk assessment applications

  10. Root Cause Analysis Following an Event at a Nuclear Installation: Reference Manual

    International Nuclear Information System (INIS)

    2015-01-01

    Following an event at a nuclear installation, it is important to determine accurately its root causes so that effective corrective actions can be implemented. As stated in IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles: “Processes must be put in place for the feedback and analysis of operating experience”. If this process is completed effectively, the probability of a similar event occurring is significantly reduced. Guidance on how to establish and implement such a process is given in IAEA Safety Standards Series No. NS-G-2.11, A System for the Feedback of Experience from Events in Nuclear Installations. To cater for the diverse nature of operating experience events, several different root cause analysis (RCA) methodologies and techniques have been developed for effective investigation and analysis. An event here is understood as any unanticipated sequence of occurrences that results in, or potentially results in, consequences to plant operation and safety. RCA is not a topic uniquely relevant to event investigators: knowledge of the concepts enhances the learning characteristics of the whole organization. This knowledge also makes a positive contribution to nuclear safety and helps to foster a culture of preventing event occurrence. This publication allows organizations to deepen their knowledge of these methodologies and techniques and also provides new organizations with a broad overview of the RCA process. It is the outcome of a coordinated effort involving the participation of experts from nuclear organizations, the energy industry and research centres in several Member States. This publication also complements IAEA Services Series No. 10, PROSPER Guidelines: Guidelines for Peer Review and for Plant Self- Assessment of Operational Experience Feedback Process, and is intended to form part of a suite of publications developing the principles set forth in these guidelines. In addition to the information and description of RCA

  11. Probabilistic Dynamics for Integrated Analysis of Accident Sequences considering Uncertain Events

    Directory of Open Access Journals (Sweden)

    Robertas Alzbutas

    2015-01-01

    Full Text Available The analytical/deterministic modelling and simulation/probabilistic methods are used separately as a rule in order to analyse the physical processes and random or uncertain events. However, in the currently used probabilistic safety assessment this is an issue. The lack of treatment of dynamic interactions between the physical processes on one hand and random events on the other hand causes the limited assessment. In general, there are a lot of mathematical modelling theories, which can be used separately or integrated in order to extend possibilities of modelling and analysis. The Theory of Probabilistic Dynamics (TPD and its augmented version based on the concept of stimulus and delay are introduced for the dynamic reliability modelling and the simulation of accidents in hybrid (continuous-discrete systems considering uncertain events. An approach of non-Markovian simulation and uncertainty analysis is discussed in order to adapt the Stimulus-Driven TPD for practical applications. The developed approach and related methods are used as a basis for a test case simulation in view of various methods applications for severe accident scenario simulation and uncertainty analysis. For this and for wider analysis of accident sequences the initial test case specification is then extended and discussed. Finally, it is concluded that enhancing the modelling of stimulated dynamics with uncertainty and sensitivity analysis allows the detailed simulation of complex system characteristics and representation of their uncertainty. The developed approach of accident modelling and analysis can be efficiently used to estimate the reliability of hybrid systems and at the same time to analyze and possibly decrease the uncertainty of this estimate.

  12. The January 2001, El Salvador event: a multi-data analysis

    Science.gov (United States)

    Vallee, M.; Bouchon, M.; Schwartz, S. Y.

    2001-12-01

    On January 13, 2001, a large normal event (Mw=7.6) occured 100 kilometers away from the Salvadorian coast (Central America) with a centroid depth of about 50km. The size of this event is surprising according to the classical idea that such events have to be much weaker than thrust events in subduction zones. We analysed this earthquake with different types of data: because teleseismic waves are the only data which offer a good azimuthal coverage, we first built a kinematic source model with P and SH waves provided by the IRIS-GEOSCOPE networks. The ambiguity between the 30o plane (plunging toward Pacific Ocean) and the 60o degree plane (plunging toward Central America) leaded us to do a parallel analysis of the two possible planes. We used a simple point-source modelling in order to define the main characteristics of the event and then used an extended source to retrieve the kinematic features of the rupture. For the 2 possible planes, this analysis reveals a downdip and northwest rupture propagation but the difference of fit remains subtle even when using the extended source. In a second part we confronted our models for the two planes with other seismological data, which are (1) regional data, (2) surface wave data through an Empirical Green Function given by a similar but much weaker earthquake which occured in July 1996 and lastly (3) nearfield data provided by Universidad Centroamericana (UCA) and Centro de Investigationes Geotecnicas (CIG). Regional data do not allow to discriminate the 2 planes neither but surface waves and especially near field data confirm that the fault plane is the steepest one plunging toward Central America. Moreover, the slight directivity toward North is confirmed by surface waves.

  13. Many multicenter trials had few events per center, requiring analysis via random-effects models or GEEs.

    Science.gov (United States)

    Kahan, Brennan C; Harhay, Michael O

    2015-12-01

    Adjustment for center in multicenter trials is recommended when there are between-center differences or when randomization has been stratified by center. However, common methods of analysis (such as fixed-effects, Mantel-Haenszel, or stratified Cox models) often require a large number of patients or events per center to perform well. We reviewed 206 multicenter randomized trials published in four general medical journals to assess the average number of patients and events per center and determine whether appropriate methods of analysis were used in trials with few patients or events per center. The median number of events per center/treatment arm combination for trials using a binary or survival outcome was 3 (interquartile range, 1-10). Sixteen percent of trials had less than 1 event per center/treatment combination, 50% fewer than 3, and 63% fewer than 5. Of the trials which adjusted for center using a method of analysis which requires a large number of events per center, 6% had less than 1 event per center-treatment combination, 25% fewer than 3, and 50% fewer than 5. Methods of analysis that allow for few events per center, such as random-effects models or generalized estimating equations (GEEs), were rarely used. Many multicenter trials contain few events per center. Adjustment for center using random-effects models or GEE with model-based (non-robust) standard errors may be beneficial in these scenarios. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Applying Petri nets in modelling the human factor

    International Nuclear Information System (INIS)

    Bedreaga, Luminita; Constntinescu, Cristina; Guzun, Basarab

    2007-01-01

    Usually, in the reliability analysis performed for complex systems, we determine the success probability to work with other performance indices, i.e. the likelihood associated with a given state. The possible values assigned to system states can be derived using inductive methods. If one wants to calculate the probability to occur a particular event in the system, then deductive methods should be applied. In the particular case of the human reliability analysis, as part of probabilistic safety analysis, the international regulatory commission have developed specific guides and procedures to perform such assessments. The paper presents the modality to obtain the human reliability quantification using the Petri nets approach. This is an efficient means to assess reliability systems because of their specific features. The examples showed in the paper are from human reliability documentation without a detailed human factor analysis (qualitative). We present human action modelling using event trees and Petri nets approach. The obtained results by these two kinds of methods are in good concordance. (authors)

  15. Detection of Abnormal Events via Optical Flow Feature Analysis

    Directory of Open Access Journals (Sweden)

    Tian Wang

    2015-03-01

    Full Text Available In this paper, a novel algorithm is proposed to detect abnormal events in video streams. The algorithm is based on the histogram of the optical flow orientation descriptor and the classification method. The details of the histogram of the optical flow orientation descriptor are illustrated for describing movement information of the global video frame or foreground frame. By combining one-class support vector machine and kernel principal component analysis methods, the abnormal events in the current frame can be detected after a learning period characterizing normal behaviors. The difference abnormal detection results are analyzed and explained. The proposed detection method is tested on benchmark datasets, then the experimental results show the effectiveness of the algorithm.

  16. Detection of Abnormal Events via Optical Flow Feature Analysis

    Science.gov (United States)

    Wang, Tian; Snoussi, Hichem

    2015-01-01

    In this paper, a novel algorithm is proposed to detect abnormal events in video streams. The algorithm is based on the histogram of the optical flow orientation descriptor and the classification method. The details of the histogram of the optical flow orientation descriptor are illustrated for describing movement information of the global video frame or foreground frame. By combining one-class support vector machine and kernel principal component analysis methods, the abnormal events in the current frame can be detected after a learning period characterizing normal behaviors. The difference abnormal detection results are analyzed and explained. The proposed detection method is tested on benchmark datasets, then the experimental results show the effectiveness of the algorithm. PMID:25811227

  17. Preterm Versus Term Children: Analysis of Sedation/Anesthesia Adverse Events and Longitudinal Risk.

    Science.gov (United States)

    Havidich, Jeana E; Beach, Michael; Dierdorf, Stephen F; Onega, Tracy; Suresh, Gautham; Cravero, Joseph P

    2016-03-01

    Preterm and former preterm children frequently require sedation/anesthesia for diagnostic and therapeutic procedures. Our objective was to determine the age at which children who are born risk for sedation/anesthesia adverse events. Our secondary objective was to describe the nature and incidence of adverse events. This is a prospective observational study of children receiving sedation/anesthesia for diagnostic and/or therapeutic procedures outside of the operating room by the Pediatric Sedation Research Consortium. A total of 57,227 patients 0 to 22 years of age were eligible for this study. All adverse events and descriptive terms were predefined. Logistic regression and locally weighted scatterplot regression were used for analysis. Preterm and former preterm children had higher adverse event rates (14.7% vs 8.5%) compared with children born at term. Our analysis revealed a biphasic pattern for the development of adverse sedation/anesthesia events. Airway and respiratory adverse events were most commonly reported. MRI scans were the most commonly performed procedures in both categories of patients. Patients born preterm are nearly twice as likely to develop sedation/anesthesia adverse events, and this risk continues up to 23 years of age. We recommend obtaining birth history during the formulation of an anesthetic/sedation plan, with heightened awareness that preterm and former preterm children may be at increased risk. Further prospective studies focusing on the etiology and prevention of adverse events in former preterm patients are warranted. Copyright © 2016 by the American Academy of Pediatrics.

  18. EVNTRE, Code System for Event Progression Analysis for PRA

    International Nuclear Information System (INIS)

    2002-01-01

    1 - Description of program or function: EVNTRE is a generalized event tree processor that was developed for use in probabilistic risk analysis of severe accident progressions for nuclear power plants. The general nature of EVNTRE makes it applicable to a wide variety of analyses that involve the investigation of a progression of events which lead to a large number of sets of conditions or scenarios. EVNTRE efficiently processes large, complex event trees. It can assign probabilities to event tree branch points in several different ways, classify pathways or outcomes into user-specified groupings, and sample input distributions of probabilities and parameters. PSTEVNT, a post-processor program used to sort and reclassify the 'binned' data output from EVNTRE and generate summary tables, is included. 2 - Methods: EVNTRE processes event trees that are cast in the form of questions or events, with multiple choice answers for each question. Split fractions (probabilities or frequencies that sum to unity) are either supplied or calculated for the branches of each question in a path-dependent manner. EVNTRE traverses the tree, enumerating the leaves of the tree and calculating their probabilities or frequencies based upon the initial probability or frequency and the split fractions for the branches taken along the corresponding path to an individual leaf. The questions in the event tree are usually grouped to address specific phases of time regimes in the progression of the scenario or severe accident. Grouping or binning of each path through the event tree in terms of a small number of characteristics or attributes is allowed. Boolean expressions of the branches taken are used to select the appropriate values of the characteristics of interest for the given path. Typically, the user specifies a cutoff tolerance for the frequency of a pathway to terminate further exploration. Multiple sets of input to an event tree can be processed by using Monte Carlo sampling to generate

  19. Human Modeling for Ground Processing Human Factors Engineering Analysis

    Science.gov (United States)

    Stambolian, Damon B.; Lawrence, Brad A.; Stelges, Katrine S.; Steady, Marie-Jeanne O.; Ridgwell, Lora C.; Mills, Robert E.; Henderson, Gena; Tran, Donald; Barth, Tim

    2011-01-01

    There have been many advancements and accomplishments over the last few years using human modeling for human factors engineering analysis for design of spacecraft. The key methods used for this are motion capture and computer generated human models. The focus of this paper is to explain the human modeling currently used at Kennedy Space Center (KSC), and to explain the future plans for human modeling for future spacecraft designs

  20. Vertically integrated analysis of human DNA. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Olson, M.

    1997-10-01

    This project has been oriented toward improving the vertical integration of the sequential steps associated with the large-scale analysis of human DNA. The central focus has been on an approach to the preparation of {open_quotes}sequence-ready{close_quotes} maps, which is referred to as multiple-complete-digest (MCD) mapping, primarily directed at cosmid clones. MCD mapping relies on simple experimental steps, supported by advanced image-analysis and map-assembly software, to produce extremely accurate restriction-site and clone-overlap maps. We believe that MCD mapping is one of the few high-resolution mapping systems that has the potential for high-level automation. Successful automation of this process would be a landmark event in genome analysis. Once other higher organisms, paving the way for cost-effective sequencing of these genomes. Critically, MCD mapping has the potential to provide built-in quality control for sequencing accuracy and to make possible a highly integrated end product even if there are large numbers of discontinuities in the actual sequence.

  1. The Use Of Computational Human Performance Modeling As Task Analysis Tool

    Energy Technology Data Exchange (ETDEWEB)

    Jacuqes Hugo; David Gertman

    2012-07-01

    During a review of the Advanced Test Reactor safety basis at the Idaho National Laboratory, human factors engineers identified ergonomic and human reliability risks involving the inadvertent exposure of a fuel element to the air during manual fuel movement and inspection in the canal. There were clear indications that these risks increased the probability of human error and possible severe physical outcomes to the operator. In response to this concern, a detailed study was conducted to determine the probability of the inadvertent exposure of a fuel element. Due to practical and safety constraints, the task network analysis technique was employed to study the work procedures at the canal. Discrete-event simulation software was used to model the entire procedure as well as the salient physical attributes of the task environment, such as distances walked, the effect of dropped tools, the effect of hazardous body postures, and physical exertion due to strenuous tool handling. The model also allowed analysis of the effect of cognitive processes such as visual perception demands, auditory information and verbal communication. The model made it possible to obtain reliable predictions of operator performance and workload estimates. It was also found that operator workload as well as the probability of human error in the fuel inspection and transfer task were influenced by the concurrent nature of certain phases of the task and the associated demand on cognitive and physical resources. More importantly, it was possible to determine with reasonable accuracy the stages as well as physical locations in the fuel handling task where operators would be most at risk of losing their balance and falling into the canal. The model also provided sufficient information for a human reliability analysis that indicated that the postulated fuel exposure accident was less than credible.

  2. Discrete event simulation tool for analysis of qualitative models of continuous processing systems

    Science.gov (United States)

    Malin, Jane T. (Inventor); Basham, Bryan D. (Inventor); Harris, Richard A. (Inventor)

    1990-01-01

    An artificial intelligence design and qualitative modeling tool is disclosed for creating computer models and simulating continuous activities, functions, and/or behavior using developed discrete event techniques. Conveniently, the tool is organized in four modules: library design module, model construction module, simulation module, and experimentation and analysis. The library design module supports the building of library knowledge including component classes and elements pertinent to a particular domain of continuous activities, functions, and behavior being modeled. The continuous behavior is defined discretely with respect to invocation statements, effect statements, and time delays. The functionality of the components is defined in terms of variable cluster instances, independent processes, and modes, further defined in terms of mode transition processes and mode dependent processes. Model construction utilizes the hierarchy of libraries and connects them with appropriate relations. The simulation executes a specialized initialization routine and executes events in a manner that includes selective inherency of characteristics through a time and event schema until the event queue in the simulator is emptied. The experimentation and analysis module supports analysis through the generation of appropriate log files and graphics developments and includes the ability of log file comparisons.

  3. Event dependent sampling of recurrent events

    DEFF Research Database (Denmark)

    Kvist, Tine Kajsa; Andersen, Per Kragh; Angst, Jules

    2010-01-01

    The effect of event-dependent sampling of processes consisting of recurrent events is investigated when analyzing whether the risk of recurrence increases with event count. We study the situation where processes are selected for study if an event occurs in a certain selection interval. Motivation...... retrospective and prospective disease course histories are used. We examine two methods to correct for the selection depending on which data are used in the analysis. In the first case, the conditional distribution of the process given the pre-selection history is determined. In the second case, an inverse...

  4. Combination of Accumulated Motion and Color Segmentation for Human Activity Analysis

    Directory of Open Access Journals (Sweden)

    Briassouli Alexia

    2008-01-01

    Full Text Available Abstract The automated analysis of activity in digital multimedia, and especially video, is gaining more and more importance due to the evolution of higher-level video processing systems and the development of relevant applications such as surveillance and sports. This paper presents a novel algorithm for the recognition and classification of human activities, which employs motion and color characteristics in a complementary manner, so as to extract the most information from both sources, and overcome their individual limitations. The proposed method accumulates the flow estimates in a video, and extracts "regions of activity" by processing their higher-order statistics. The shape of these activity areas can be used for the classification of the human activities and events taking place in a video and the subsequent extraction of higher-level semantics. Color segmentation of the active and static areas of each video frame is performed to complement this information. The color layers in the activity and background areas are compared using the earth mover's distance, in order to achieve accurate object segmentation. Thus, unlike much existing work on human activity analysis, the proposed approach is based on general color and motion processing methods, and not on specific models of the human body and its kinematics. The combined use of color and motion information increases the method robustness to illumination variations and measurement noise. Consequently, the proposed approach can lead to higher-level information about human activities, but its applicability is not limited to specific human actions. We present experiments with various real video sequences, from sports and surveillance domains, to demonstrate the effectiveness of our approach.

  5. Combination of Accumulated Motion and Color Segmentation for Human Activity Analysis

    Directory of Open Access Journals (Sweden)

    Ioannis Kompatsiaris

    2008-03-01

    Full Text Available The automated analysis of activity in digital multimedia, and especially video, is gaining more and more importance due to the evolution of higher-level video processing systems and the development of relevant applications such as surveillance and sports. This paper presents a novel algorithm for the recognition and classification of human activities, which employs motion and color characteristics in a complementary manner, so as to extract the most information from both sources, and overcome their individual limitations. The proposed method accumulates the flow estimates in a video, and extracts “regions of activity” by processing their higher-order statistics. The shape of these activity areas can be used for the classification of the human activities and events taking place in a video and the subsequent extraction of higher-level semantics. Color segmentation of the active and static areas of each video frame is performed to complement this information. The color layers in the activity and background areas are compared using the earth mover's distance, in order to achieve accurate object segmentation. Thus, unlike much existing work on human activity analysis, the proposed approach is based on general color and motion processing methods, and not on specific models of the human body and its kinematics. The combined use of color and motion information increases the method robustness to illumination variations and measurement noise. Consequently, the proposed approach can lead to higher-level information about human activities, but its applicability is not limited to specific human actions. We present experiments with various real video sequences, from sports and surveillance domains, to demonstrate the effectiveness of our approach.

  6. Analysis of area events as part of probabilistic safety assessment for Romanian TRIGA SSR 14 MW reactor

    International Nuclear Information System (INIS)

    Mladin, D.; Stefan, I.

    2005-01-01

    The international experience has shown that the external events could be an important contributor to plant/ reactor risk. For this reason such events have to be included in the PSA studies. In the context of PSA for nuclear facilities, external events are defined as events originating from outside the plant, but with the potential to create an initiating event at the plant. To support plant safety assessment, PSA can be used to find methods for identification of vulnerable features of the plant and to suggest modifications in order to mitigate the impact of external events or the producing of initiating events. For that purpose, probabilistic assessment of area events concerning fire and flooding risk and impact is necessary. Due to the relatively large power level amongst research reactors, the approach to safety analysis of Romanian 14 MW TRIGA benefits from an ongoing PSA project. In this context, treatment of external events should be considered. The specific tasks proposed for the complete evaluation of area event analysis are: identify the rooms important for facility safety, determine a relative area event risk index for these rooms and a relative area event impact index if the event occurs, evaluate the rooms specific area event frequency, determine the rooms contribution to reactor hazard state frequencies, analyze power supply and room dependencies of safety components (as pumps, motor operated valves). The fire risk analysis methodology is based on Berry's method [1]. This approach provides a systematic procedure to carry out a relative index of different rooms. The factors, which affect the fire probability, are: personal presence in the room, number and type of ignition sources, type and area of combustibles, fuel available in the room, fuel location, and ventilation. The flooding risk analysis is based on the amount of piping in the room. For accuracy of the information regarding piping a facility walk-about is necessary. In case of flooding risk

  7. Probabilistic safety analysis for fire events for the NPP Isar 2

    International Nuclear Information System (INIS)

    Schmaltz, H.; Hristodulidis, A.

    2007-01-01

    The 'Probabilistic Safety Analysis for Fire Events' (Fire-PSA KKI2) for the NPP Isar 2 was performed in addition to the PSA for full power operation and considers all possible events which can be initiated due to a fire. The aim of the plant specific Fire-PSA was to perform a quantitative assessment of fire events during full power operation, which is state of the art. Based on simplistic assumptions referring to the fire induced failures, the influence of system- and component-failures on the frequency of the core damage states was analysed. The Fire-PSA considers events, which will result due to fire-induced failures of equipment on the one hand in a SCRAM and on the other hand in events, which will not have direct operational effects but because of the fire-induced failure of safety related installations the plant will be shut down as a precautionary measure. These events are considered because they may have a not negligible influence on the frequency of core damage states in case of failures during the plant shut down because of the reduced redundancy of safety related systems. (orig.)

  8. Is human failure a stochastic process?

    International Nuclear Information System (INIS)

    Dougherty, Ed M.

    1997-01-01

    Human performance results in failure events that occur with a risk-significant frequency. System analysts have taken for granted the random (stochastic) nature of these events in engineering assessments such as risk assessment. However, cognitive scientists and error technologists, at least those who have interest in human reliability, have, over the recent years, claimed that human error does not need this stochastic framework. Yet they still use the language appropriate to stochastic processes. This paper examines the potential for the stochastic nature of human failure production as the basis for human reliability analysis. It distinguishes and leaves to others, however, the epistemic uncertainties over the possible probability models for the real variability of human performance

  9. Culture Representation in Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    David Gertman; Julie Marble; Steven Novack

    2006-12-01

    Understanding human-system response is critical to being able to plan and predict mission success in the modern battlespace. Commonly, human reliability analysis has been used to predict failures of human performance in complex, critical systems. However, most human reliability methods fail to take culture into account. This paper takes an easily understood state of the art human reliability analysis method and extends that method to account for the influence of culture, including acceptance of new technology, upon performance. The cultural parameters used to modify the human reliability analysis were determined from two standard industry approaches to cultural assessment: Hofstede’s (1991) cultural factors and Davis’ (1989) technology acceptance model (TAM). The result is called the Culture Adjustment Method (CAM). An example is presented that (1) reviews human reliability assessment with and without cultural attributes for a Supervisory Control and Data Acquisition (SCADA) system attack, (2) demonstrates how country specific information can be used to increase the realism of HRA modeling, and (3) discusses the differences in human error probability estimates arising from cultural differences.

  10. Human event-related brain potentials to auditory periodic noise stimuli.

    Science.gov (United States)

    Kaernbach, C; Schröger, E; Gunter, T C

    1998-02-06

    Periodic noise is perceived as different from ordinary non-repeating noise due to the involvement of echoic memory. Since this stimulus does not contain simple physical cues (such as onsets or spectral shape) that might obscure sensory memory interpretations, it is a valuable tool to study sensory memory functions. We demonstrated for the first time that the processing of periodic noise can be tapped by event-related brain potentials (ERPs). Human subjects received repeating segments of noise embedded in non-repeating noise. They were instructed to detect the periodicity inherent to the stimulation. We observed a central negativity time-locked on the periodic segment that correlated to the subjects behavioral performance in periodicity detection. It is argued that the ERP result indicates an enhancement of sensory-specific processing.

  11. A task analysis-linked approach for integrating the human factor in reliability assessments of nuclear power plants

    International Nuclear Information System (INIS)

    Ryan, T.G.

    1988-01-01

    This paper describes an emerging Task Analysis-Linked Evaluation Technique (TALENT) for assessing the contributions of human error to nuclear power plant systems unreliability and risk. Techniques such as TALENT are emerging as a recognition that human error is a primary contributor to plant safety, however, it has been a peripheral consideration to data in plant reliability evaluations. TALENT also recognizes that involvement of persons with behavioral science expertise is required to support plant reliability and risk analyses. A number of state-of-knowledge human reliability analysis tools are also discussed which support the TALENT process. The core of TALENT is comprised of task, timeline and interface analysis data which provide the technology base for event and fault tree development, serve as criteria for selecting and evaluating performance shaping factors, and which provide a basis for auditing TALENT results. Finally, programs and case studies used to refine the TALENT process are described along with future research needs in the area. (author)

  12. The role of human performance in the safety complex plants' operation

    International Nuclear Information System (INIS)

    Preda, Irina Aida; Lazar, Roxana Elena; Croitoru, Cornelia

    1999-01-01

    According to statistics, about 20-30% from the failures occurred in the plants are caused directly or indirectly by human errors. Furthermore, it was established that 10-15% of the global failures are related with the human errors. These are mainly due to the wrong actions, maintenance errors, and misinterpretation of instruments. The human performance is influenced by: professional ability, complexity and danger to the plant experience in the working place, level of skills, events in personal and/or professional life, discipline, social ambience, somatic health. The human performances' assessment in the probabilistic safety assessment offers the possibility of evaluation of human contribution to the events sequences outcome. Not all the human errors have impact on the system. A human error may be recovered before the unwanted consequences had been occurred on system. This paper presents the possibilities to use the probabilistic method (event tree, fault tree) to identify the solutions for human reliability improved in order to minimize the risk in industrial plants' operation. Also, the human error types and their causes are defined and the 'decision tree method' as technique in our analysis for human reliability assessment is presented. The exemplification of human error analysis method was achieved based on operation data for Valcea Heavy Water Pilot Plant. As initiating event for the accident state 'the steam supply interruption' event has been considered. The human errors' contribution was analysed for the accident sequence with the worst consequences. (authors)

  13. Analysis of manufacturing based on object oriented discrete event simulation

    Directory of Open Access Journals (Sweden)

    Eirik Borgen

    1990-01-01

    Full Text Available This paper describes SIMMEK, a computer-based tool for performing analysis of manufacturing systems, developed at the Production Engineering Laboratory, NTH-SINTEF. Its main use will be in analysis of job shop type of manufacturing. But certain facilities make it suitable for FMS as well as a production line manufacturing. This type of simulation is very useful in analysis of any types of changes that occur in a manufacturing system. These changes may be investments in new machines or equipment, a change in layout, a change in product mix, use of late shifts, etc. The effects these changes have on for instance the throughput, the amount of VIP, the costs or the net profit, can be analysed. And this can be done before the changes are made, and without disturbing the real system. Simulation takes into consideration, unlike other tools for analysis of manufacturing systems, uncertainty in arrival rates, process and operation times, and machine availability. It also shows the interaction effects a job which is late in one machine, has on the remaining machines in its route through the layout. It is these effects that cause every production plan not to be fulfilled completely. SIMMEK is based on discrete event simulation, and the modeling environment is object oriented. The object oriented models are transformed by an object linker into data structures executable by the simulation kernel. The processes of the entity objects, i.e. the products, are broken down to events and put into an event list. The user friendly graphical modeling environment makes it possible for end users to build models in a quick and reliable way, using terms from manufacturing. Various tests and a check of model logic are helpful functions when testing validity of the models. Integration with software packages, with business graphics and statistical functions, is convenient in the result presentation phase.

  14. Analysis of core damage frequency from internal events: Peach Bottom, Unit 2

    International Nuclear Information System (INIS)

    Kolaczkowski, A.M.; Lambright, J.A.; Ferrell, W.L.; Cathey, N.G.; Najafi, B.; Harper, F.T.

    1986-10-01

    This document contains the internal event initiated accident sequence analyses for Peach Bottom, Unit 2; one of the reference plants being examined as part of the NUREG-1150 effort by the Nuclear Regulatory Commission. NUREG-1150 will document the risk of a selected group of nuclear power plants. As part of that work, this report contains the overall core damage frequency estimate for Peach Bottom, Unit 2, and the accompanying plant damage state frequencies. Sensitivity and uncertainty analyses provided additional insights regarding the dominant contributors to the Peach Bottom core damage frequency estimate. The mean core damage frequency at Peach Bottom was calculated to be 8.2E-6. Station blackout type accidents (loss of all ac power) were found to dominate the overall results. Anticipated Transient Without Scram accidents were also found to be non-negligible contributors. The numerical results are largely driven by common mode failure probability estimates and to some extent, human error. Because of significant data and analysis uncertainties in these two areas (important, for instance, to the most dominant scenario in this study), it is recommended that the results of the uncertainty and sensitivity analyses be considered before any actions are taken based on this analysis

  15. Re-presentations of space in Hollywood movies: an event-indexing analysis.

    Science.gov (United States)

    Cutting, James; Iricinschi, Catalina

    2015-03-01

    Popular movies present chunk-like events (scenes and subscenes) that promote episodic, serial updating of viewers' representations of the ongoing narrative. Event-indexing theory would suggest that the beginnings of new scenes trigger these updates, which in turn require more cognitive processing. Typically, a new movie event is signaled by an establishing shot, one providing more background information and a longer look than the average shot. Our analysis of 24 films reconfirms this. More important, we show that, when returning to a previously shown location, the re-establishing shot reduces both context and duration while remaining greater than the average shot. In general, location shifts dominate character and time shifts in event segmentation of movies. In addition, over the last 70 years re-establishing shots have become more like the noninitial shots of a scene. Establishing shots have also approached noninitial shot scales, but not their durations. Such results suggest that film form is evolving, perhaps to suit more rapid encoding of narrative events. Copyright © 2014 Cognitive Science Society, Inc.

  16. A hydrological analysis of the 4 November 2011 event in Genoa

    Directory of Open Access Journals (Sweden)

    F. Silvestro

    2012-09-01

    Full Text Available On the 4 November 2011 a flash flood event hit the area of Genoa with dramatic consequences. Such an event represents, from the meteorological and hydrological perspective, a paradigm of flash floods in the Mediterranean environment.

    The hydro-meteorological probabilistic forecasting system for small and medium size catchments in use at the Civil Protection Centre of Liguria region exhibited excellent performances for the event, by predicting, 24–48 h in advance, the potential level of risk associated with the forecast. It greatly helped the decision makers in issuing a timely and correct alert.

    In this work we present the operational outputs of the system provided during the Liguria events and the post event hydrological modelling analysis that has been carried out accounting also for the crowd sourcing information and data. We discuss the benefit of the implemented probabilistic systems for decision-making under uncertainty, highlighting how, in this case, the multi-catchment approach used for predicting floods in small basins has been crucial.

  17. Automatic Video-based Analysis of Human Motion

    DEFF Research Database (Denmark)

    Fihl, Preben

    The human motion contains valuable information in many situations and people frequently perform an unconscious analysis of the motion of other people to understand their actions, intentions, and state of mind. An automatic analysis of human motion will facilitate many applications and thus has...... received great interest from both industry and research communities. The focus of this thesis is on video-based analysis of human motion and the thesis presents work within three overall topics, namely foreground segmentation, action recognition, and human pose estimation. Foreground segmentation is often...... the first important step in the analysis of human motion. By separating foreground from background the subsequent analysis can be focused and efficient. This thesis presents a robust background subtraction method that can be initialized with foreground objects in the scene and is capable of handling...

  18. Analysis of meiosis regulators in human gonads

    DEFF Research Database (Denmark)

    Jørgensen, Anne; Nielsen, John E; Jensen, Martin Blomberg

    2012-01-01

    The mitosis-meiosis switch is a key event in the differentiation of germ cells. In humans, meiosis is initiated in fetal ovaries, whereas in testes meiotic entry is inhibited until puberty. The purpose of this study was to examine the expression pattern of meiosis regulators in human gonads...... with their role in initiation and progression of meiosis. The putative meiosis inhibitors, CYP26B1 and NANOS2, were primarily expressed in Leydig cells and spermatocytes, respectively. In conclusion, the expression pattern of the investigated meiotic regulators is largely conserved in the human gonads compared...... with rodents, but with some minor differences, such as a stable expression of CYP26B1 in human fetal ovaries. The sexually dimorphic expression pattern of DMRT1 indicates a similar role in the mitosis-meiosis switch in human gonads as previously demonstrated in mice. The biological importance of the changes...

  19. Data driven analysis of rain events: feature extraction, clustering, microphysical /macro physical relationship

    Science.gov (United States)

    Djallel Dilmi, Mohamed; Mallet, Cécile; Barthes, Laurent; Chazottes, Aymeric

    2017-04-01

    The study of rain time series records is mainly carried out using rainfall rate or rain accumulation parameters estimated on a fixed integration time (typically 1 min, 1 hour or 1 day). In this study we used the concept of rain event. In fact, the discrete and intermittent natures of rain processes make the definition of some features inadequate when defined on a fixed duration. Long integration times (hour, day) lead to mix rainy and clear air periods in the same sample. Small integration time (seconds, minutes) will lead to noisy data with a great sensibility to detector characteristics. The analysis on the whole rain event instead of individual short duration samples of a fixed duration allows to clarify relationships between features, in particular between macro physical and microphysical ones. This approach allows suppressing the intra-event variability partly due to measurement uncertainties and allows focusing on physical processes. An algorithm based on Genetic Algorithm (GA) and Self Organising Maps (SOM) is developed to obtain a parsimonious characterisation of rain events using a minimal set of variables. The use of self-organizing map (SOM) is justified by the fact that it allows to map a high dimensional data space in a two-dimensional space while preserving as much as possible the initial space topology in an unsupervised way. The obtained SOM allows providing the dependencies between variables and consequently removing redundant variables leading to a minimal subset of only five features (the event duration, the rain rate peak, the rain event depth, the event rain rate standard deviation and the absolute rain rate variation of order 0.5). To confirm relevance of the five selected features the corresponding SOM is analyzed. This analysis shows clearly the existence of relationships between features. It also shows the independence of the inter-event time (IETp) feature or the weak dependence of the Dry percentage in event (Dd%e) feature. This confirms

  20. An analysis of operational experience during low power and shutdown and a plan for addressing human reliability assessment issues

    International Nuclear Information System (INIS)

    Barriere, M.; Luckas, W.; Whitehead, D.; Ramey-Smith, A.

    1994-06-01

    Recent nuclear power plant events (e.g. Chernobyl, Diablo Canyon, and Vogtle) and US Nuclear Regulatory Commission (NRC) reports (e.g. NUREG-1449) have led to concerns regarding human reliability during low power and shutdown (LP ampersand S) conditions and limitations of human reliability analysis (HRA) methodologies in adequately representing the LP ampersand S environment. As a result of these concerns, the NRC initiated two parallel research projects to assess the influence of LP ampersand S conditions on human reliability through an analysis of operational experience at pressurized water reactors (PWRs) an boiling water reactors (BWRs). These research projects, performed by Brookhaven National Laboratory for PWRS, and Sandia National Laboratories for BWRs, identified unique aspects of human performance during LP ampersand S conditions and provided a program plan for research and development necessary to improve existing HRA methodologies. This report documents the results of the analysis of LP ampersand S operating experience and describes the improved HRA program plan

  1. A human factors data bank for French nuclear power plants

    International Nuclear Information System (INIS)

    Villemeur, A.; Mosneron-Dupin, F.; Bouissou, M.; Meslin, T.

    1986-01-01

    CONFUCIUS is a computerized data bank developed by Electricite de France to study human factors in nuclear power plants. A detailed and homogeneous grouping of described operation and maintenance errors as well as of performance times is possible with CONFUCIUS. It also incorporates a selection of statistical treatment softwares. Readily usable and modifiable, the system can easily evolve. It allows a wide range of applications (safety analysis, event analysis, training, human factors engineering, probabilistic analysis). Data derived from the analysis of significant events reported in power plants and from the analysis of simulator tests are used as inputs into this data bank

  2. Limitations in simulator time-based human reliability analysis methods

    International Nuclear Information System (INIS)

    Wreathall, J.

    1989-01-01

    Developments in human reliability analysis (HRA) methods have evolved slowly. Current methods are little changed from those of almost a decade ago, particularly in the use of time-reliability relationships. While these methods were suitable as an interim step, the time (and the need) has come to specify the next evolution of HRA methods. As with any performance-oriented data source, power plant simulator data have no direct connection to HRA models. Errors reported in data are normal deficiencies observed in human performance; failures are events modeled in probabilistic risk assessments (PRAs). Not all errors cause failures; not all failures are caused by errors. Second, the times at which actions are taken provide no measure of the likelihood of failures to act correctly within an accident scenario. Inferences can be made about human reliability, but they must be made with great care. Specific limitations are discussed. Simulator performance data are useful in providing qualitative evidence of the variety of error types and their potential influences on operating systems. More work is required to combine recent developments in the psychology of error with the qualitative data collected at stimulators. Until data become openly available, however, such an advance will not be practical

  3. Analysis of events related to cracks and leaks in the reactor coolant pressure boundary

    Energy Technology Data Exchange (ETDEWEB)

    Ballesteros, Antonio, E-mail: Antonio.Ballesteros-Avila@ec.europa.eu [JRC-IET: Institute for Energy and Transport of the Joint Research Centre of the European Commission, Postbus 2, NL-1755 ZG Petten (Netherlands); Sanda, Radian; Peinador, Miguel; Zerger, Benoit [JRC-IET: Institute for Energy and Transport of the Joint Research Centre of the European Commission, Postbus 2, NL-1755 ZG Petten (Netherlands); Negri, Patrice [IRSN: Institut de Radioprotection et de Sûreté Nucléaire (France); Wenke, Rainer [GRS: Gesellschaft für Anlagen- und Reaktorsicherheit (GRS) mbH (Germany)

    2014-08-15

    Highlights: • The important role of Operating Experience Feedback is emphasised. • Events relating to cracks and leaks in the reactor coolant pressure boundary are analysed. • A methodology for event investigation is described. • Some illustrative results of the analysis of events for specific components are presented. - Abstract: The presence of cracks and leaks in the reactor coolant pressure boundary may jeopardise the safe operation of nuclear power plants. Analysis of cracks and leaks related events is an important task for the prevention of their recurrence, which should be performed in the context of activities on Operating Experience Feedback. In response to this concern, the EU Clearinghouse operated by the JRC-IET supports and develops technical and scientific work to disseminate the lessons learned from past operating experience. In particular, concerning cracks and leaks, the studies carried out in collaboration with IRSN and GRS have allowed to identify the most sensitive areas to degradation in the plant primary system and to elaborate recommendations for upgrading the maintenance, ageing management and inspection programmes. An overview of the methodology used in the analysis of cracks and leaks related events is presented in this paper, together with the relevant results obtained in the study.

  4. The eigenmode analysis of human motion

    International Nuclear Information System (INIS)

    Park, Juyong; Lee, Deok-Sun; González, Marta C

    2010-01-01

    Rapid advances in modern communication technology are enabling the accumulation of large-scale, high-resolution observational data of the spatiotemporal movements of humans. Classification and prediction of human mobility based on the analysis of such data has great potential in applications such as urban planning in addition to being a subject of theoretical interest. A robust theoretical framework is therefore required to study and properly understand human motion. Here we perform the eigenmode analysis of human motion data gathered from mobile communication records, which allows us to explore the scaling properties and characteristics of human motion

  5. Hybrid instrument applied to human reliability study in event of loss of external electric power in a nuclear power plant; Instrumento hibrido aplicado ao estudo da confiabilidade humana em evento de perda de energia eletrica externa em usina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Eduardo Ferraz

    2015-04-01

    The study projects in highly complex installations involves robust modeling, supported by conceptual and mathematical tools, to carry out systematic research and structured the different risk scenarios that can lead to unwanted events from occurring equipment failures or human errors. In the context of classical modeling, the Probabilistic Safety Analysis (PSA) seeks to provide qualitative and quantitative information about the project particularity and their operational facilities, including the identification of factors or scenarios that contribute to the risk and consequent comparison options for increasing safety. In this context, the aim of the thesis is to develop a hybrid instrument (CPP-HI) innovative, from the integrated modeling techniques of Failure Mode and Effect Analysis (FMEA), concepts of Human Reliability Analysis and Probabilistic Composition of Preferences (PCP). In support of modeling and validation of the CPP-HI, a simulation was performed on a triggering event 'Loss of External Electric Power' - PEEE, in a Nuclear Power plant. The results were simulated in a virtual environment (sensitivity analysis) and are robust to the study of Human Reliability Analysis (HRA) in the context of the PSA. (author)

  6. Integration of risk matrix and event tree analysis: a natural stone ...

    Indian Academy of Sciences (India)

    M Kemal Özfirat

    2017-09-27

    Sep 27, 2017 ... Different types of accidents may occur in natural stone facilities during movement, dimensioning, cutting ... are numerous risk analysis methods such as preliminary ..... machine type and maintenance (MM) event, block control.

  7. Making sense of root cause analysis investigations of surgery-related adverse events.

    Science.gov (United States)

    Cassin, Bryce R; Barach, Paul R

    2012-02-01

    This article discusses the limitations of root cause analysis (RCA) for surgical adverse events. Making sense of adverse events involves an appreciation of the unique features in a problematic situation, which resist generalization to other contexts. The top priority of adverse event investigations must be to inform the design of systems that help clinicians to adapt and respond effectively in real time to undesirable combinations of design, performance, and circumstance. RCAs can create opportunities in the clinical workplace for clinicians to reflect on local barriers and identify enablers of safe and reliable outcomes. Copyright © 2012 Elsevier Inc. All rights reserved.

  8. Disruptive Event Biosphere Dose Conversion Factor Analysis

    Energy Technology Data Exchange (ETDEWEB)

    M. Wasiolek

    2004-09-08

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the volcanic ash exposure scenario, and the development of dose factors for calculating inhalation dose during volcanic eruption. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed descriptions of the model input parameters, their development and the relationship between the parameters and specific features, events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the volcanic ash exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and from the five analyses that develop parameter values for the biosphere model (BSC 2004 [DIRS 169671]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; and BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis''. The objective of this

  9. Disruptive Event Biosphere Dose Conversion Factor Analysis

    International Nuclear Information System (INIS)

    M. Wasiolek

    2004-01-01

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the volcanic ash exposure scenario, and the development of dose factors for calculating inhalation dose during volcanic eruption. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed descriptions of the model input parameters, their development and the relationship between the parameters and specific features, events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the volcanic ash exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and from the five analyses that develop parameter values for the biosphere model (BSC 2004 [DIRS 169671]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; and BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis''. The objective of this analysis was to develop the BDCFs for the volcanic ash

  10. Workshop on the use of PRA methodology for the analysis of reactor events and operational data: Proceedings

    International Nuclear Information System (INIS)

    Rasmuson, D.M.

    1992-06-01

    A workshop entitled ''The Use of PRA Methodology for the Analysis of Reactor Events and Operational Data'' was held on January 29--30, 1992 in Annapolis, Maryland. Over 50 participants from the NRC, its contractors, and others participated in the meetings. During the first day, presentations were made by invited speakers to discuss issues in relevant topics. On the second day, discussion groups were held to focus on three areas: risk significance of operational events, industry risk profile and generic concerns, and risk monitoring and risk-based performance indicators. Important considerations identified from the workshop are the following: Improve the Accident Sequence Precursor models and data. Improve the SCSS and NPRDS (e.g., by adding detailed performance information on selected components, by improving narratives on failure causes). Develop risk-based performance indicators. Use risk insights to help focus trending and performance analyses of components, systems, initiators, and sequences. Improve the statistical quality of trending and performance analyses. Flag implications of special conditions (e.g., external events, containment performance) during data studies. Trend common cause and human performance using appropriate models to obtain a better understanding of the impact and causes of failure. Develop a method for producing an industry risk profile

  11. Event-by-event jet quenching

    Energy Technology Data Exchange (ETDEWEB)

    Fries, R.J.; Rodriguez, R.; Ramirez, E.

    2010-08-14

    High momentum jets and hadrons can be used as probes for the quark gluon plasma (QGP) formed in nuclear collisions at high energies. We investigate the influence of fluctuations in the fireball on jet quenching observables by comparing propagation of light quarks and gluons through averaged, smooth QGP fireballs with event-by-event jet quenching using realistic inhomogeneous fireballs. We find that the transverse momentum and impact parameter dependence of the nuclear modification factor R{sub AA} can be fit well in an event-by-event quenching scenario within experimental errors. However the transport coefficient {cflx q} extracted from fits to the measured nuclear modification factor R{sub AA} in averaged fireballs underestimates the value from event-by-event calculations by up to 50%. On the other hand, after adjusting {cflx q} to fit R{sub AA} in the event-by-event analysis we find residual deviations in the azimuthal asymmetry v{sub 2} and in two-particle correlations, that provide a possible faint signature for a spatial tomography of the fireball. We discuss a correlation function that is a measure for spatial inhomogeneities in a collision and can be constrained from data.

  12. Event-by-event jet quenching

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, R. [Cyclotron Institute and Physics Department, Texas A and M University, College Station, TX 77843 (United States); Fries, R.J., E-mail: rjfries@comp.tamu.ed [Cyclotron Institute and Physics Department, Texas A and M University, College Station, TX 77843 (United States); RIKEN/BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973 (United States); Ramirez, E. [Physics Department, University of Texas El Paso, El Paso, TX 79968 (United States)

    2010-09-27

    High momentum jets and hadrons can be used as probes for the quark gluon plasma (QGP) formed in nuclear collisions at high energies. We investigate the influence of fluctuations in the fireball on jet quenching observables by comparing propagation of light quarks and gluons through averaged, smooth QGP fireballs with event-by-event jet quenching using realistic inhomogeneous fireballs. We find that the transverse momentum and impact parameter dependence of the nuclear modification factor R{sub AA} can be fit well in an event-by-event quenching scenario within experimental errors. However the transport coefficient q extracted from fits to the measured nuclear modification factor R{sub AA} in averaged fireballs underestimates the value from event-by-event calculations by up to 50%. On the other hand, after adjusting q to fit R{sub AA} in the event-by-event analysis we find residual deviations in the azimuthal asymmetry v{sub 2} and in two-particle correlations, that provide a possible faint signature for a spatial tomography of the fireball. We discuss a correlation function that is a measure for spatial inhomogeneities in a collision and can be constrained from data.

  13. Expert judgment in analysis of human and organizational behaviour at nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Reiman, L [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland). Dept. of Nuclear Safety

    1994-12-01

    Probabilistic safety assessment (PSA) of a nuclear power plant includes an assessment of the probability of each event sequence that can lead to a reactor core damage and of their consequences. Despite increasing maturity of PSA methods, there are still several problems in their use. These include the assessment of human reliability and the impact of organizational factors on plant safety. The assessment of both these issues is based on expert judgment. Therefore, the use of expert judgment in analysis of human and organizational behaviour was studied theoretically and in practical case studies in this thesis. Human errors were analysed in two case studies. In the first study cognitive actions of control room operators were analysed. For this purpose methods were developed for the qualitative and quantitative phases of the analysis. Errors of test and maintenance personnel were analysed in the second case study. Especially the dependence of errors between sequential tasks performed in redundant subsystems of a safety system was studied. A method to assess organizational behaviour was developed and applied in the third case study. The three case studies demonstrated that expert judgment can be used in the analysis of human reliability and organizational behaviour taking into account the observations made and the remarks presented in the study. However, significant uncertainties are related with expert judgment. Recommendations are presented concerning the use of different methods. Also, some insights are presented into how reliance on expert judgment could be reduced. (241 refs., 20 figs., 36 tabs.).

  14. Expert judgment in analysis of human and organizational behaviour at nuclear power plants

    International Nuclear Information System (INIS)

    Reiman, L.

    1994-12-01

    Probabilistic safety assessment (PSA) of a nuclear power plant includes an assessment of the probability of each event sequence that can lead to a reactor core damage and of their consequences. Despite increasing maturity of PSA methods, there are still several problems in their use. These include the assessment of human reliability and the impact of organizational factors on plant safety. The assessment of both these issues is based on expert judgment. Therefore, the use of expert judgment in analysis of human and organizational behaviour was studied theoretically and in practical case studies in this thesis. Human errors were analysed in two case studies. In the first study cognitive actions of control room operators were analysed. For this purpose methods were developed for the qualitative and quantitative phases of the analysis. Errors of test and maintenance personnel were analysed in the second case study. Especially the dependence of errors between sequential tasks performed in redundant subsystems of a safety system was studied. A method to assess organizational behaviour was developed and applied in the third case study. The three case studies demonstrated that expert judgment can be used in the analysis of human reliability and organizational behaviour taking into account the observations made and the remarks presented in the study. However, significant uncertainties are related with expert judgment. Recommendations are presented concerning the use of different methods. Also, some insights are presented into how reliance on expert judgment could be reduced. (241 refs., 20 figs., 36 tabs.)

  15. Investigation and analysis of hydrogen ignition and explosion events in foreign nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Okuda, Yasunori [Institute of Nuclear Safety System, Inc., Mihama, Fukui (Japan)

    2002-09-01

    Reports about hydrogen ignition and explosion events in foreign nuclear power plants from 1980 to 2001 were investigated, and 31 events were identified. Analysis showed that they were categorized in (1) outer leakage ignition events and (2) inner accumulation ignition events. The dominant event for PWR (pressurized water reactor) was outer leakage ignition in the main generator, and in BWR (boiling water reactor) it was inner accumulation ignition in the off-gas system. The outer leakage ignition was a result of work process failure with the ignition source, operator error, or main generator hydrogen leakage. The inner accumulation ignition events were caused by equipment failure or insufficient monitoring. With careful preventive measures, the factors leading to these events could be eliminated. (author)

  16. Root-Cause Analysis of a Potentially Sentinel Transfusion Event: Lessons for Improvement of Patient Safety

    Directory of Open Access Journals (Sweden)

    Ali Reza Jeddian

    2012-09-01

    Full Text Available Errors prevention and patient safety in transfusion medicine are a serious concern. Errors can occur at any step in transfusion and evaluation of their root causes can be helpful for preventive measures. Root cause analysis as a structured and systematic approach can be used for identification of underlying causes of adverse events. To specify system vulnerabilities and illustrate the potential of such an approach, we describe the root cause analysis of a case of transfusion error in emergency ward that could have been fatal. After reporting of the mentioned event, through reviewing records and interviews with the responsible personnel, the details of the incident were elaborated. Then, an expert panel meeting was held to define event timeline and the care and service delivery problems and discuss their underlying causes, safeguards and preventive measures. Root cause analysis of the mentioned event demonstrated that certain defects of the system and the ensuing errors were main causes of the event. It also points out systematic corrective actions. It can be concluded that health care organizations should endeavor to provide opportunities to discuss errors and adverse events and introduce preventive measures to find areas where resources need to be allocated to improve patient safety.

  17. Analysis of unintended events in hospitals: inter-rater reliability of constructing causal trees and classifying root causes

    NARCIS (Netherlands)

    Smits, M.; Janssen, J.; Vet, de H.C.W.; Zwaan, L.; Timmermans, D.R.M.; Groenewegen, P.P.; Wagner, C.

    2009-01-01

    BACKGROUND: Root cause analysis is a method to examine causes of unintended events. PRISMA (Prevention and Recovery Information System for Monitoring and Analysis: is a root cause analysis tool. With PRISMA, events are described in causal trees and root causes are subsequently classified with the

  18. Analysis of unintended events in hospitals : inter-rater reliability of constructing causal trees and classifying root causes

    NARCIS (Netherlands)

    Smits, M.; Janssen, J.; Vet, R. de; Zwaan, L.; Groenewegen, P.P.; Timmermans, D.

    2009-01-01

    Background. Root cause analysis is a method to examine causes of unintended events. PRISMA (Prevention and Recovery Information System for Monitoring and Analysis) is a root cause analysis tool. With PRISMA, events are described in causal trees and root causes are subsequently classified with the

  19. Analysis of unintended events in hospitals: inter-rater reliability of constructing causal trees and classifying root causes.

    NARCIS (Netherlands)

    Smits, M.; Janssen, J.; Vet, R. de; Zwaan, L.; Timmermans, D.; Groenewegen, P.; Wagner, C.

    2009-01-01

    Background: Root cause analysis is a method to examine causes of unintended events. PRISMA (Prevention and Recovery Information System for Monitoring and Analysis) is a root cause analysis tool. With PRISMA, events are described in causal trees and root causes are subsequently classified with the

  20. Human Milk Analysis Using Mid-Infrared Spectroscopy.

    Science.gov (United States)

    Groh-Wargo, Sharon; Valentic, Jennifer; Khaira, Sharmeel; Super, Dennis M; Collin, Marc

    2016-04-01

    The composition of human milk is known to vary with length of gestation, stage of lactation, and other factors. Human milk contains all nutrients required for infant health but requires fortification to meet the needs of low-birth-weight infants. Without a known nutrient profile of the mother's milk or donor milk fed to a baby, the composition of the fortified product is only an estimate. Human milk analysis has the potential to improve the nutrition care of high-risk newborns by increasing the information about human milk composition. Equipment to analyze human milk is available, and the technology is rapidly evolving. This pilot study compares mid-infrared (MIR) spectroscopy to reference laboratory milk analysis. After obtaining informed consent, we collected human milk samples from mothers of infants weighing milk obtained by MIR vs reference laboratory analysis. MIR analysis appears to provide an accurate assessment of macronutrient content in expressed human milk from mothers of preterm infants. The small sample size of this study limits confidence in the results. Measurement of lactose is confounded by the presence of oligosaccharides. Human milk analysis is a potentially useful tool for establishing an individualized fortification plan. © 2015 American Society for Parenteral and Enteral Nutrition.

  1. Recurring events - Volume 2

    International Nuclear Information System (INIS)

    2003-04-01

    known, thus the actions taken were not effective in preventing recurrence of an event, - The contributing factors or causes of the event were not taken into account in defining the actions to be taken. Several good practices were identified to prevent recurring events. These practices are part of related guides provided by national and international bodies. Some of these are: - NPPs should analyse recurring events in-depth, in order to identify root causes and contributing factors to prevent further recurrence. The specific factors that failed to prevent recurrence should be investigated and identified (that is, why prior operating experience was not effectively applied). - For minor events, trend analyses should be performed to monitor the frequency of component failures (which may be unavoidable) or the frequency of minor human performance problems (which may indicate weaknesses in error prevention processes and programs). - Analysis of external operating experiences from other NPPs should be strengthened to broaden the basis for preventive measures; - Actions taken after events should be assessed regarding their effectiveness in preventing recurrence of similar events. Subsequent to the workshop, a more detailed search of reports of operating experience, including IRS and other reports from national sources, resulted in the determination of a number of recurring categories: - Loss of RHR at mid-loop (in the 1999 report also); - BWR instability (in the 1999 report also); - PWR vessel corrosion due to boric acid effects; - Hydrogen detonation in BWR piping; - Steam Generator Tube Rupture; - Multiple valve failures in ECCS; - Service Water Failure due to Marine Biofouling (in the 1999 report also); - System Level Failures with Human Factors Considerations; - Strainer Clogging (sources of emergency injection or recirculation). Five conclusions were established on the basis of the workshop and the recurring event analysis: Conclusion 1: Recurring events continue to be

  2. A human reliability analysis (HRA) method for identifying and assessing the error of commission (EOC) from a diagnosis failure

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jae Whan; Jung, Won Dea; Park, Jin Yun; Kang, Dae Il

    2005-01-01

    The study deals with a method for systematically identifying and assessing the EOC events that might be caused from a diagnosis failure or misdiagnosis of the expected events in accident scenarios of nuclear power plants. The method for EOC identification and assessment consists of three steps: analysis of the potential for a diagnosis failure (or misdiagnosis), identification of the EOC events from the diagnosis failure, quantitative assessment of the identified EOC events. As a tool for analysing a diagnosis failure, the MisDiagnosis Tree Analysis (MDTA) technique is proposed with the taxonomy of misdiagnosis causes. Also, the guidance on the identification of EOC events and the classification system and data are given for quantitiative assessment. As an applicaton of the proposed method, the EOCs identification and assessment for Younggwang 3 and 4 plants and their impact on the plant risk were performed. As the result, six events or event sequences were considered for diagnosis failures and about 20 new Human Failure Events (HFEs) involving EOCs were identified. According to the assessment of the risk impact of the identified HFEs, they increase the CDF by 11.4 % of the current CDF value, which corresponds to 10.2 % of the new CDF. The small loss of coolant accident (SLOCA) turned out to be a major contributor to the increase of CDF resulting in 9.2 % increaseof the current CDF.

  3. Human Reliability Analysis for Design: Using Reliability Methods for Human Factors Issues

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Laurids Boring

    2010-11-01

    This paper reviews the application of human reliability analysis methods to human factors design issues. An application framework is sketched in which aspects of modeling typically found in human reliability analysis are used in a complementary fashion to the existing human factors phases of design and testing. The paper provides best achievable practices for design, testing, and modeling. Such best achievable practices may be used to evaluate and human system interface in the context of design safety certifications.

  4. Human Reliability Analysis for Design: Using Reliability Methods for Human Factors Issues

    International Nuclear Information System (INIS)

    Boring, Ronald Laurids

    2010-01-01

    This paper reviews the application of human reliability analysis methods to human factors design issues. An application framework is sketched in which aspects of modeling typically found in human reliability analysis are used in a complementary fashion to the existing human factors phases of design and testing. The paper provides best achievable practices for design, testing, and modeling. Such best achievable practices may be used to evaluate and human system interface in the context of design safety certifications.

  5. Economic Multipliers and Mega-Event Analysis

    OpenAIRE

    Victor Matheson

    2004-01-01

    Critics of economic impact studies that purport to show that mega-events such as the Olympics bring large benefits to the communities “lucky” enough to host them frequently cite the use of inappropriate multipliers as a primary reason why these impact studies overstate the true economic gains to the hosts of these events. This brief paper shows in a numerical example how mega-events may lead to inflated multipliers and exaggerated claims of economic benefits.

  6. Vulnerability analysis of a PWR to an external event

    International Nuclear Information System (INIS)

    Aruety, S.; Ilberg, D.; Hertz, Y.

    1980-01-01

    The Vulnerability of a Nuclear Power Plant (NPP) to external events is affected by several factors such as: the degree of redundancy of the reactor systems, subsystems and components; the separation of systems provided in the general layout; the extent of the vulnerable area, i.e., the area which upon being affected by an external event will result in system failure; and the time required to repair or replace the systems, when allowed. The present study offers a methodology, using Probabilistic Safety Analysis, to evaluate the relative importance of the above parameters in reducing the vulnerability of reactor safety systems. Several safety systems of typical PWR's are analyzed as examples. It was found that the degree of redundancy and physical separation of the systems has the most prominent effect on the vulnerability of the NPP

  7. The limiting events transient analysis by RETRAN02 and VIPRE01 for an ABWR

    International Nuclear Information System (INIS)

    Tsai Chiungwen; Shih Chunkuan; Wang Jongrong; Lin Haotzu; Jin Jiunan; Cheng Suchin

    2009-01-01

    This paper describes the transient analysis of generator load rejection (LR) and One Turbine Control Valve Closure (OTCVC) events for Lungmen nuclear power plant (LMNPP). According to the Critical Power Ratio (CPR) criterion, the Preliminary Safety Analysis Report (PSAR) concluded that LR and OTCVC are the first and second limiting events respectively. In addition, the fuel type is changed from GE12 to GE14 now. It's necessary to re-analyze these two events for safety consideration. In this study, to quantify the impact to reactor, the difference of initial critical power ratio (ICPR) and minimum critical power ratio (MCPR), ie. ΔCPR is calculated. The ΔCPRs of the LR and OTCVC events are calculated with the combination of RETRAN02 and VIPRE01 codes. In RETRAN02 calculation, a thermal-hydraulic model was prepared for the transient analysis. The data including upper plenum pressure, core inlet flow, normalized power, and axial power shapes during transient are furthermore submitted into VIPRE01 for ΔCPR calculation. In VIPRE01 calculation, there was a hot channel model built to simulate the hottest fuel bundle. Based on the thermal-hydraulic data from RETRAN02, the ΔCPRs are calculated by VIPRE01 hot channel model. Additionally, the different TCV control modes are considered to study the influence of different TCV closure curves on transient behavior. Meanwhile, sensitivity studies including different initial system pressure and different initial power/flow conditions are also considered. Based on this analysis, the maximum ΔCPRs for LR and OTCVC are 0.162 and 0.191 respectively. According CPR criterion, the result shows that the impact caused by OTCVC event leads to be larger than LR event. (author)

  8. Analysis of syntactic and semantic features for fine-grained event-spatial understanding in outbreak news reports

    Directory of Open Access Journals (Sweden)

    Chanlekha Hutchatai

    2010-03-01

    Full Text Available Abstract Background Previous studies have suggested that epidemiological reasoning needs a fine-grained modelling of events, especially their spatial and temporal attributes. While the temporal analysis of events has been intensively studied, far less attention has been paid to their spatial analysis. This article aims at filling the gap concerning automatic event-spatial attribute analysis in order to support health surveillance and epidemiological reasoning. Results In this work, we propose a methodology that provides a detailed analysis on each event reported in news articles to recover the most specific locations where it occurs. Various features for recognizing spatial attributes of the events were studied and incorporated into the models which were trained by several machine learning techniques. The best performance for spatial attribute recognition is very promising; 85.9% F-score (86.75% precision/85.1% recall. Conclusions We extended our work on event-spatial attribute recognition by focusing on machine learning techniques, which are CRF, SVM, and Decision tree. Our approach avoided the costly development of an external knowledge base by employing the feature sources that can be acquired locally from the analyzed document. The results showed that the CRF model performed the best. Our study indicated that the nearest location and previous event location are the most important features for the CRF and SVM model, while the location extracted from the verb's subject is the most important to the Decision tree model.

  9. Development on quantitative safety analysis method of accident scenario. The automatic scenario generator development for event sequence construction of accident

    International Nuclear Information System (INIS)

    Kojima, Shigeo; Onoue, Akira; Kawai, Katsunori

    1998-01-01

    This study intends to develop a more sophisticated tool that will advance the current event tree method used in all PSA, and to focus on non-catastrophic events, specifically a non-core melt sequence scenario not included in an ordinary PSA. In the non-catastrophic event PSA, it is necessary to consider various end states and failure combinations for the purpose of multiple scenario construction. Therefore it is anticipated that an analysis work should be reduced and automated method and tool is required. A scenario generator that can automatically handle scenario construction logic and generate the enormous size of sequences logically identified by state-of-the-art methodology was developed. To fulfill the scenario generation as a technical tool, a simulation model associated with AI technique and graphical interface, was introduced. The AI simulation model in this study was verified for the feasibility of its capability to evaluate actual systems. In this feasibility study, a spurious SI signal was selected to test the model's applicability. As a result, the basic capability of the scenario generator could be demonstrated and important scenarios were generated. The human interface with a system and its operation, as well as time dependent factors and their quantification in scenario modeling, was added utilizing human scenario generator concept. Then the feasibility of an improved scenario generator was tested for actual use. Automatic scenario generation with a certain level of credibility, was achieved by this study. (author)

  10. Human Errors - A Taxonomy for Describing Human Malfunction in Industrial Installations

    DEFF Research Database (Denmark)

    Rasmussen, Jens

    1982-01-01

    This paper describes the definition and the characteristics of human errors. Different types of human behavior are classified, and their relation to different error mechanisms are analyzed. The effect of conditioning factors related to affective, motivating aspects of the work situation as well...... as physiological factors are also taken into consideration. The taxonomy for event analysis, including human malfunction, is presented. Possibilities for the prediction of human error are discussed. The need for careful studies in actual work situations is expressed. Such studies could provide a better...

  11. A Research Roadmap for Computation-Based Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Boring, Ronald [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mandelli, Diego [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey [Idaho National Lab. (INL), Idaho Falls, ID (United States); Smith, Curtis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Groth, Katrina [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-08-01

    The United States (U.S.) Department of Energy (DOE) is sponsoring research through the Light Water Reactor Sustainability (LWRS) program to extend the life of the currently operating fleet of commercial nuclear power plants. The Risk Informed Safety Margin Characterization (RISMC) research pathway within LWRS looks at ways to maintain and improve the safety margins of these plants. The RISMC pathway includes significant developments in the area of thermalhydraulics code modeling and the development of tools to facilitate dynamic probabilistic risk assessment (PRA). PRA is primarily concerned with the risk of hardware systems at the plant; yet, hardware reliability is often secondary in overall risk significance to human errors that can trigger or compound undesirable events at the plant. This report highlights ongoing efforts to develop a computation-based approach to human reliability analysis (HRA). This computation-based approach differs from existing static and dynamic HRA approaches in that it: (i) interfaces with a dynamic computation engine that includes a full scope plant model, and (ii) interfaces with a PRA software toolset. The computation-based HRA approach presented in this report is called the Human Unimodels for Nuclear Technology to Enhance Reliability (HUNTER) and incorporates in a hybrid fashion elements of existing HRA methods to interface with new computational tools developed under the RISMC pathway. The goal of this research effort is to model human performance more accurately than existing approaches, thereby minimizing modeling uncertainty found in current plant risk models.

  12. A Research Roadmap for Computation-Based Human Reliability Analysis

    International Nuclear Information System (INIS)

    Boring, Ronald; Mandelli, Diego; Joe, Jeffrey; Smith, Curtis; Groth, Katrina

    2015-01-01

    The United States (U.S.) Department of Energy (DOE) is sponsoring research through the Light Water Reactor Sustainability (LWRS) program to extend the life of the currently operating fleet of commercial nuclear power plants. The Risk Informed Safety Margin Characterization (RISMC) research pathway within LWRS looks at ways to maintain and improve the safety margins of these plants. The RISMC pathway includes significant developments in the area of thermalhydraulics code modeling and the development of tools to facilitate dynamic probabilistic risk assessment (PRA). PRA is primarily concerned with the risk of hardware systems at the plant; yet, hardware reliability is often secondary in overall risk significance to human errors that can trigger or compound undesirable events at the plant. This report highlights ongoing efforts to develop a computation-based approach to human reliability analysis (HRA). This computation-based approach differs from existing static and dynamic HRA approaches in that it: (i) interfaces with a dynamic computation engine that includes a full scope plant model, and (ii) interfaces with a PRA software toolset. The computation-based HRA approach presented in this report is called the Human Unimodels for Nuclear Technology to Enhance Reliability (HUNTER) and incorporates in a hybrid fashion elements of existing HRA methods to interface with new computational tools developed under the RISMC pathway. The goal of this research effort is to model human performance more accurately than existing approaches, thereby minimizing modeling uncertainty found in current plant risk models.

  13. DISRUPTIVE EVENT BIOSPHERE DOSE CONVERSION FACTOR ANALYSIS

    International Nuclear Information System (INIS)

    M.A. Wasiolek

    2005-01-01

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the volcanic ash exposure scenario, and the development of dose factors for calculating inhalation dose during volcanic eruption. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The Biosphere Model Report (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed descriptions of the model input parameters, their development and the relationship between the parameters and specific features, events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the volcanic ash exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and from the five analyses that develop parameter values for the biosphere model (BSC 2005 [DIRS 172827]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; and BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis'' (Figure 1-1). The objective of this analysis was to develop the BDCFs for the volcanic

  14. Dynamic event Tress applied to sequences Full Spectrum LOCA. Calculating the frequency of excedeence of damage by integrated Safety Analysis Methodology

    International Nuclear Information System (INIS)

    Gomez-Magan, J. J.; Fernandez, I.; Gil, J.; Marrao, H.; Queral, C.; Gonzalez-Cadelo, J.; Montero-Mayorga, J.; Rivas, J.; Ibane-Llano, C.; Izquierdo, J. M.; Sanchez-Perea, M.; Melendez, E.; Hortal, J.

    2013-01-01

    The Integrated Safety Analysis (ISA) methodology, developed by the Spanish Nuclear Safety council (CSN), has been applied to obtain the dynamic Event Trees (DETs) for full spectrum Loss of Coolant Accidents (LOCAs) of a Westinghouse 3-loop PWR plant. The purpose of this ISA application is to obtain the Damage Excedence Frequency (DEF) for the LOCA Event Tree by taking into account the uncertainties in the break area and the operator actuation time needed to cool down and de pressurize reactor coolant system by means of steam generator. Simulations are performed with SCAIS, a software tool which includes a dynamic coupling with MAAP thermal hydraulic code. The results show the capability of the ISA methodology to obtain the DEF taking into account the time uncertainty in human actions. (Author)

  15. Shock events and flood risk management: a media analysis of the institutional long-term effects of flood events in the Netherlands and Poland

    Directory of Open Access Journals (Sweden)

    Maria Kaufmann

    2016-12-01

    Full Text Available Flood events that have proven to create shock waves in society, which we will call shock events, can open windows of opportunity that allow different actor groups to introduce new ideas. Shock events, however, can also strengthen the status quo. We will take flood events as our object of study. Whereas others focus mainly on the immediate impact and disaster management, we will focus on the long-term impact on and resilience of flood risk governance arrangements. Over the last 25 years, both the Netherlands and Poland have suffered several flood-related events. These triggered strategic and institutional changes, but to different degrees. In a comparative analysis these endogenous processes, i.e., the importance of framing of the flood event, its exploitation by different actor groups, and the extent to which arrangements are actually changing, are examined. In line with previous research, our analysis revealed that shock events test the capacity to resist and bounce back and provide opportunities for adapting and learning. They "open up" institutional arrangements and make them more susceptible to change, increasing the opportunity for adaptation. In this way they can facilitate a shift toward different degrees of resilience, i.e., by adjusting the current strategic approach or by moving toward another strategic approach. The direction of change is influenced by the actors and the frames they introduce, and their ability to increase the resonance of the frame. The persistence of change seems to be influenced by the evolution of the initial management approach, the availability of resources, or the willingness to allocate resources.

  16. Thousands of exon skipping events differentiate among splicing patterns in sixteen human tissues [v2; ref status: indexed, http://f1000r.es/2dl

    Directory of Open Access Journals (Sweden)

    Liliana Florea

    2013-11-01

    Full Text Available Alternative splicing is widely recognized for its roles in regulating genes and creating gene diversity. However, despite many efforts, the repertoire of gene splicing variation is still incompletely characterized, even in humans. Here we describe a new computational system, ASprofile, and its application to RNA-seq data from Illumina’s Human Body Map project (>2.5 billion reads.  Using the system, we identified putative alternative splicing events in 16 different human tissues, which provide a dynamic picture of splicing variation across the tissues. We detected 26,989 potential exon skipping events representing differences in splicing patterns among the tissues. A large proportion of the events (>60% were novel, involving new exons (~3000, new introns (~16000, or both. When tracing these events across the sixteen tissues, only a small number (4-7% appeared to be differentially expressed (‘switched’ between two tissues, while 30-45% showed little variation, and the remaining 50-65% were not present in one or both tissues compared.  Novel exon skipping events appeared to be slightly less variable than known events, but were more tissue-specific. Our study represents the first effort to build a comprehensive catalog of alternative splicing in normal human tissues from RNA-seq data, while providing insights into the role of alternative splicing in shaping tissue transcriptome differences. The catalog of events and the ASprofile software are freely available from the Zenodo repository (http://zenodo.org/record/7068; doi:10.5281/zenodo.7068 and from our web site http://ccb.jhu.edu/software/ASprofile.

  17. The development of human factors technologies -The development of human behaviour analysis techniques-

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jung Woon; Lee, Yong Heui; Park, Keun Ok; Chun, Se Woo; Suh, Sang Moon; Park, Jae Chang [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1995-07-01

    In order to contribute to human error reduction through the studies on human-machine interaction in nuclear power plants, this project has objectives to develop SACOM(Simulation Analyzer with a Cognitive Operator Model) and techniques for human error analysis and application. In this year, we studied the followings: (1) Site investigation of operator tasks, (2) Development of operator task micro structure and revision of micro structure, (3) Development of knowledge representation software and SACOM prototype, (4) Development of performance assessment methodologies in task simulation and analysis of the effects of performance shaping factors. human error analysis and application techniques> (1) Classification of error shaping factors(ESFs) and development of software for ESF evaluation, (2) Analysis of human error occurrences and revision of analysis procedure, (3) Experiment for human error data collection using a compact nuclear simulator, (4) Development of a prototype data base system of the analyzed information on trip cases. 55 figs, 23 tabs, 33 refs. (Author).

  18. Significant aspects of the external event analysis methodology of the Jose Cabrera NPP PSA

    International Nuclear Information System (INIS)

    Barquin Duena, A.; Martin Martinez, A.R.; Boneham, P.S.; Ortega Prieto, P.

    1994-01-01

    This paper describes the following advances in the methodology for Analysis of External Events in the PSA of the Jose Cabrera NPP: In the Fire Analysis, a version of the COMPBRN3 CODE, modified by Empresarios Agrupados according to the guidelines of Appendix D of the NUREG/CR-5088, has been used. Generic cases were modelled and general conclusions obtained, applicable to fire propagation in closed areas. The damage times obtained were appreciably lower than those obtained with the previous version of the code. The Flood Analysis methodology is based on the construction of event trees to represent flood propagation dependent on the condition of the communication paths between areas, and trees showing propagation stages as a function of affected areas and damaged mitigation equipment. To determine temporary evolution of the flood area level, the CAINZO-EA code has been developed, adapted to specific plant characteristics. In both the Fire and Flood Analyses a quantification methodology has been adopted, which consists of analysing the damages caused at each stage of growth or propagation and identifying, in the Internal Events models, the gates, basic events or headers to which safe failure (probability 1) due to damages is assigned. (Author)

  19. Advanced Reactor Passive System Reliability Demonstration Analysis for an External Event

    Directory of Open Access Journals (Sweden)

    Matthew Bucknor

    2017-03-01

    Full Text Available Many advanced reactor designs rely on passive systems to fulfill safety functions during accident sequences. These systems depend heavily on boundary conditions to induce a motive force, meaning the system can fail to operate as intended because of deviations in boundary conditions, rather than as the result of physical failures. Furthermore, passive systems may operate in intermediate or degraded modes. These factors make passive system operation difficult to characterize within a traditional probabilistic framework that only recognizes discrete operating modes and does not allow for the explicit consideration of time-dependent boundary conditions. Argonne National Laboratory has been examining various methodologies for assessing passive system reliability within a probabilistic risk assessment for a station blackout event at an advanced small modular reactor. This paper provides an overview of a passive system reliability demonstration analysis for an external event. Considering an earthquake with the possibility of site flooding, the analysis focuses on the behavior of the passive Reactor Cavity Cooling System following potential physical damage and system flooding. The assessment approach seeks to combine mechanistic and simulation-based methods to leverage the benefits of the simulation-based approach without the need to substantially deviate from conventional probabilistic risk assessment techniques. Although this study is presented as only an example analysis, the results appear to demonstrate a high level of reliability of the Reactor Cavity Cooling System (and the reactor system in general for the postulated transient event.

  20. Advanced reactor passive system reliability demonstration analysis for an external event

    Energy Technology Data Exchange (ETDEWEB)

    Bucknor, Matthew; Grabaskas, David; Brunett, Acacia J.; Grelle, Austin [Argonne National Laboratory, Argonne (United States)

    2017-03-15

    Many advanced reactor designs rely on passive systems to fulfill safety functions during accident sequences. These systems depend heavily on boundary conditions to induce a motive force, meaning the system can fail to operate as intended because of deviations in boundary conditions, rather than as the result of physical failures. Furthermore, passive systems may operate in intermediate or degraded modes. These factors make passive system operation difficult to characterize within a traditional probabilistic framework that only recognizes discrete operating modes and does not allow for the explicit consideration of time-dependent boundary conditions. Argonne National Laboratory has been examining various methodologies for assessing passive system reliability within a probabilistic risk assessment for a station blackout event at an advanced small modular reactor. This paper provides an overview of a passive system reliability demonstration analysis for an external event. Considering an earthquake with the possibility of site flooding, the analysis focuses on the behavior of the passive Reactor Cavity Cooling System following potential physical damage and system flooding. The assessment approach seeks to combine mechanistic and simulation-based methods to leverage the benefits of the simulation-based approach without the need to substantially deviate from conventional probabilistic risk assessment techniques. Although this study is presented as only an example analysis, the results appear to demonstrate a high level of reliability of the Reactor Cavity Cooling System (and the reactor system in general) for the postulated transient event.

  1. Advanced reactor passive system reliability demonstration analysis for an external event

    International Nuclear Information System (INIS)

    Bucknor, Matthew; Grabaskas, David; Brunett, Acacia J.; Grelle, Austin

    2017-01-01

    Many advanced reactor designs rely on passive systems to fulfill safety functions during accident sequences. These systems depend heavily on boundary conditions to induce a motive force, meaning the system can fail to operate as intended because of deviations in boundary conditions, rather than as the result of physical failures. Furthermore, passive systems may operate in intermediate or degraded modes. These factors make passive system operation difficult to characterize within a traditional probabilistic framework that only recognizes discrete operating modes and does not allow for the explicit consideration of time-dependent boundary conditions. Argonne National Laboratory has been examining various methodologies for assessing passive system reliability within a probabilistic risk assessment for a station blackout event at an advanced small modular reactor. This paper provides an overview of a passive system reliability demonstration analysis for an external event. Considering an earthquake with the possibility of site flooding, the analysis focuses on the behavior of the passive Reactor Cavity Cooling System following potential physical damage and system flooding. The assessment approach seeks to combine mechanistic and simulation-based methods to leverage the benefits of the simulation-based approach without the need to substantially deviate from conventional probabilistic risk assessment techniques. Although this study is presented as only an example analysis, the results appear to demonstrate a high level of reliability of the Reactor Cavity Cooling System (and the reactor system in general) for the postulated transient event

  2. An Initiating-Event Analysis for PSA of Hanul Units 3 and 4: Results and Insights

    International Nuclear Information System (INIS)

    Kim, Dong-San; Park, Jin Hee

    2015-01-01

    As a part of the PSA, an initiating-event (IE) analysis was newly performed by considering the current state of knowledge and the requirements of the ASME/ANS probabilistic risk assessment (PRA) standard related to IE analysis. This paper describes the methods of, results and some insights from the IE analysis for the PSA of the Hanul units 3 and 4. In this study, as a part of the PSA for the Hanul units 3 and 4, an initiating-event (IE) analysis was newly performed by considering the current state of knowledge and the requirements of the ASME/ANS probabilistic risk assessment (PRA) standard. In comparison with the previous IE analysis, this study performed a more systematic and detailed analysis to identify potential initiating events, and calculated the IE frequencies by using the state-of-the-art methods and the latest data. As a result, not a few IE frequencies are quite different from the previous frequencies, which can change the major accident sequences obtained from the quantification of the PSA model

  3. Correlation Relationship of Performance Shaping Factors (PSFs) for Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Bheka, M. Khumalo; Kim, Jonghyun [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2014-10-15

    At TMI-2, operators permitted thousands of gallons of water to escape from the reactor plant before realizing that the coolant pumps were behaving abnormally. The coolant pumps were then turned off, which in turn led to the destruction of the reactor itself as cooling was completely lost within the core. Human also plays a role in many aspects of complex systems e.g. in design and manufacture of hardware, interface between human and system and also in maintaining such systems as well as for coping with unusual events that place the NPP system at a risk. This is why human reliability analysis (HRA) - an aspect of risk assessments which systematically identifies and analyzes the causes and consequences of human decisions and actions - is important in nuclear power plant operations. It either upgrades or degrades human performance; therefore it has an impact on the possibility of error. These PSFs can be used in various HRA methods to estimate Human Error Probabilities (HEPs). There are many current HRA methods who propose sets of PSFs for normal operation mode of NPP. Some of these PSFs in the sets have some degree of dependency and overlap. Overlapping PSFs introduce error in HEP evaluations due to the fact that some elements are counted more than once in data; this skews the relationship amongst PSF and masks the way that the elements interact to affect performance. This study uses a causal model that represents dependencies and relationships amongst PSFs for HEP evaluation during normal NPP operational states. The model is built taking into consideration the dependencies among PSFs and thus eliminating overlap. The use of an interdependent model of PSFs is expected to produce more accurate HEPs compared to other current methods. PSF sets produced in this study can be further used as nodes (variables) and directed arcs (causal influence between nodes) in HEP evaluation methods such as Bayesian belief (BN) networks. This study was done to estimate the relationships

  4. Simulation and Non-Simulation Based Human Reliability Analysis Approaches

    Energy Technology Data Exchange (ETDEWEB)

    Boring, Ronald Laurids [Idaho National Lab. (INL), Idaho Falls, ID (United States); Shirley, Rachel Elizabeth [Idaho National Lab. (INL), Idaho Falls, ID (United States); Joe, Jeffrey Clark [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mandelli, Diego [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-12-01

    Part of the U.S. Department of Energy’s Light Water Reactor Sustainability (LWRS) Program, the Risk-Informed Safety Margin Characterization (RISMC) Pathway develops approaches to estimating and managing safety margins. RISMC simulations pair deterministic plant physics models with probabilistic risk models. As human interactions are an essential element of plant risk, it is necessary to integrate human actions into the RISMC risk model. In this report, we review simulation-based and non-simulation-based human reliability assessment (HRA) methods. Chapter 2 surveys non-simulation-based HRA methods. Conventional HRA methods target static Probabilistic Risk Assessments for Level 1 events. These methods would require significant modification for use in dynamic simulation of Level 2 and Level 3 events. Chapter 3 is a review of human performance models. A variety of methods and models simulate dynamic human performance; however, most of these human performance models were developed outside the risk domain and have not been used for HRA. The exception is the ADS-IDAC model, which can be thought of as a virtual operator program. This model is resource-intensive but provides a detailed model of every operator action in a given scenario, along with models of numerous factors that can influence operator performance. Finally, Chapter 4 reviews the treatment of timing of operator actions in HRA methods. This chapter is an example of one of the critical gaps between existing HRA methods and the needs of dynamic HRA. This report summarizes the foundational information needed to develop a feasible approach to modeling human interactions in the RISMC simulations.

  5. Estimation of initiating event distribution at nuclear power plants by Bayesian procedure

    International Nuclear Information System (INIS)

    Chen Guangming

    1995-01-01

    Initiating events at nuclear power plants such as human errors or components failures may lead to a nuclear accident. The study of the frequency of these events or the distribution of the failure rate is necessary in probabilistic risk assessment for nuclear power plants. This paper presents Bayesian modelling methods for the analysis of the distribution of the failure rate. The method can also be utilized in other related fields especially where the data is sparse. An application of the Bayesian modelling in the analysis of distribution of the time to recover Loss of Off-Site Power ( LOSP) is discussed in the paper

  6. Erectile dysfunction and cardiovascular events in diabetic men: a meta-analysis of observational studies.

    Directory of Open Access Journals (Sweden)

    Tomohide Yamada

    Full Text Available BACKGROUND: Several studies have shown that erectile dysfunction (ED influences the risk of cardiovascular events (CV events. However, a meta-analysis of the overall risk of CV events associated with ED in patients with diabetes has not been performed. METHODOLOGY/PRINCIPAL FINDINGS: We searched MEDLINE and the Cochrane Library for pertinent articles (including references published between 1951 and April 22, 2012. English language reports of original observational cohort studies and cross-sectional studies were included. Pooled effect estimates were obtained by random effects meta-analysis. A total of 3,791 CV events were reported in 3 cohort studies and 9 cross-sectional studies (covering 22,586 subjects. Across the cohort studies, the overall odds ratio (OR of diabetic men with ED versus those without ED was 1.74 (95% confidence interval [CI]: 1.34-2.27; P0.05. Moreover, meta-regression analysis found no relationship between the method used to assess ED (questionnaire or interview, mean age, mean hemoglobin A(1c, mean body mass index, or mean duration of diabetes and the risk of CV events or CHD. In the cross-sectional studies, the OR of diabetic men with ED versus those without ED was 3.39 (95% CI: 2.58-4.44; P<0.001 for CV events (N = 9, 3.43 (95% CI: 2.46-4.77; P<0.001 for CHD (N = 7, and 2.63 (95% CI: 1.41-4.91; P = 0.002 for peripheral vascular disease (N = 5. CONCLUSION/SIGNIFICANCE: ED was associated with an increased risk of CV events in diabetic patients. Prevention and early detection of cardiovascular disease are important in the management of diabetes, especially in view of the rapid increase in its prevalence.

  7. Human Performance Modeling for Dynamic Human Reliability Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Boring, Ronald Laurids [Idaho National Laboratory; Joe, Jeffrey Clark [Idaho National Laboratory; Mandelli, Diego [Idaho National Laboratory

    2015-08-01

    Part of the U.S. Department of Energy’s (DOE’s) Light Water Reac- tor Sustainability (LWRS) Program, the Risk-Informed Safety Margin Charac- terization (RISMC) Pathway develops approaches to estimating and managing safety margins. RISMC simulations pair deterministic plant physics models with probabilistic risk models. As human interactions are an essential element of plant risk, it is necessary to integrate human actions into the RISMC risk framework. In this paper, we review simulation based and non simulation based human reliability analysis (HRA) methods. This paper summarizes the founda- tional information needed to develop a feasible approach to modeling human in- teractions in RISMC simulations.

  8. The interplay between human population dynamics and flooding in Bangladesh: a spatial analysis

    Science.gov (United States)

    di Baldassarre, G.; Yan, K.; Ferdous, MD. R.; Brandimarte, L.

    2014-09-01

    In Bangladesh, socio-economic and hydrological processes are both extremely dynamic and inter-related. Human population patterns are often explained as a response, or adaptation strategy, to physical events, e.g. flooding, salt-water intrusion, and erosion. Meanwhile, these physical processes are exacerbated, or mitigated, by diverse human interventions, e.g. river diversion, levees and polders. In this context, this paper describes an attempt to explore the complex interplay between floods and societies in Bangladeshi floodplains. In particular, we performed a spatially-distributed analysis of the interactions between the dynamics of human settlements and flood inundation patterns. To this end, we used flooding simulation results from inundation modelling, LISFLOOD-FP, as well as global datasets of population distribution data, such as the Gridded Population of the World (20 years, from 1990 to 2010) and HYDE datasets (310 years, from 1700 to 2010). The outcomes of this work highlight the behaviour of Bangladeshi floodplains as complex human-water systems and indicate the need to go beyond the traditional narratives based on one-way cause-effects, e.g. climate change leading to migrations.

  9. Procedure for conducting probabilistic safety assessment: level 1 full power internal event analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Won Dae; Lee, Y. H.; Hwang, M. J. [and others

    2003-07-01

    This report provides guidance on conducting a Level I PSA for internal events in NPPs, which is based on the method and procedure that was used in the PSA for the design of Korea Standard Nuclear Plants (KSNPs). Level I PSA is to delineate the accident sequences leading to core damage and to estimate their frequencies. It has been directly used for assessing and modifying the system safety and reliability as a key and base part of PSA. Also, Level I PSA provides insights into design weakness and into ways of preventing core damage, which in most cases is the precursor to accidents leading to major accidents. So Level I PSA has been used as the essential technical bases for risk-informed application in NPPs. The report consists six major procedural steps for Level I PSA; familiarization of plant, initiating event analysis, event tree analysis, system fault tree analysis, reliability data analysis, and accident sequence quantification. The report is intended to assist technical persons performing Level I PSA for NPPs. A particular aim is to promote a standardized framework, terminology and form of documentation for PSAs. On the other hand, this report would be useful for the managers or regulatory persons related to risk-informed regulation, and also for conducting PSA for other industries.

  10. Statistical analysis of events related to emergency diesel generators failures in the nuclear industry

    Energy Technology Data Exchange (ETDEWEB)

    Kančev, Duško, E-mail: dusko.kancev@ec.europa.eu [European Commission, DG-JRC, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Duchac, Alexander; Zerger, Benoit [European Commission, DG-JRC, Institute for Energy and Transport, P.O. Box 2, NL-1755 ZG Petten (Netherlands); Maqua, Michael [Gesellschaft für Anlagen-und-Reaktorsicherheit (GRS) mbH, Schwetnergasse 1, 50667 Köln (Germany); Wattrelos, Didier [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), BP 17 - 92262 Fontenay-aux-Roses Cedex (France)

    2014-07-01

    Highlights: • Analysis of operating experience related to emergency diesel generators events at NPPs. • Four abundant operating experience databases screened. • Delineating important insights and conclusions based on the operating experience. - Abstract: This paper is aimed at studying the operating experience related to emergency diesel generators (EDGs) events at nuclear power plants collected from the past 20 years. Events related to EDGs failures and/or unavailability as well as all the supporting equipment are in the focus of the analysis. The selected operating experience was analyzed in detail in order to identify the type of failures, attributes that contributed to the failure, failure modes potential or real, discuss risk relevance, summarize important lessons learned, and provide recommendations. The study in this particular paper is tightly related to the performing of statistical analysis of the operating experience. For the purpose of this study EDG failure is defined as EDG failure to function on demand (i.e. fail to start, fail to run) or during testing, or an unavailability of an EDG, except of unavailability due to regular maintenance. The Gesellschaft für Anlagen und Reaktorsicherheit mbH (GRS) and Institut de Radioprotection et de Sûreté Nucléaire (IRSN) databases as well as the operating experience contained in the IAEA/NEA International Reporting System for Operating Experience and the U.S. Licensee Event Reports were screened. The screening methodology applied for each of the four different databases is presented. Further on, analysis aimed at delineating the causes, root causes, contributing factors and consequences are performed. A statistical analysis was performed related to the chronology of events, types of failures, the operational circumstances of detection of the failure and the affected components/subsystems. The conclusions and results of the statistical analysis are discussed. The main findings concerning the testing

  11. Statistical analysis of events related to emergency diesel generators failures in the nuclear industry

    International Nuclear Information System (INIS)

    Kančev, Duško; Duchac, Alexander; Zerger, Benoit; Maqua, Michael; Wattrelos, Didier

    2014-01-01

    Highlights: • Analysis of operating experience related to emergency diesel generators events at NPPs. • Four abundant operating experience databases screened. • Delineating important insights and conclusions based on the operating experience. - Abstract: This paper is aimed at studying the operating experience related to emergency diesel generators (EDGs) events at nuclear power plants collected from the past 20 years. Events related to EDGs failures and/or unavailability as well as all the supporting equipment are in the focus of the analysis. The selected operating experience was analyzed in detail in order to identify the type of failures, attributes that contributed to the failure, failure modes potential or real, discuss risk relevance, summarize important lessons learned, and provide recommendations. The study in this particular paper is tightly related to the performing of statistical analysis of the operating experience. For the purpose of this study EDG failure is defined as EDG failure to function on demand (i.e. fail to start, fail to run) or during testing, or an unavailability of an EDG, except of unavailability due to regular maintenance. The Gesellschaft für Anlagen und Reaktorsicherheit mbH (GRS) and Institut de Radioprotection et de Sûreté Nucléaire (IRSN) databases as well as the operating experience contained in the IAEA/NEA International Reporting System for Operating Experience and the U.S. Licensee Event Reports were screened. The screening methodology applied for each of the four different databases is presented. Further on, analysis aimed at delineating the causes, root causes, contributing factors and consequences are performed. A statistical analysis was performed related to the chronology of events, types of failures, the operational circumstances of detection of the failure and the affected components/subsystems. The conclusions and results of the statistical analysis are discussed. The main findings concerning the testing

  12. Hybrid Human-Computing Distributed Sense-Making: Extending the SOA Paradigm for Dynamic Adjudication and Optimization of Human and Computer Roles

    Science.gov (United States)

    Rimland, Jeffrey C.

    2013-01-01

    In many evolving systems, inputs can be derived from both human observations and physical sensors. Additionally, many computation and analysis tasks can be performed by either human beings or artificial intelligence (AI) applications. For example, weather prediction, emergency event response, assistive technology for various human sensory and…

  13. Features, Events, and Processes: Disruptive Events

    Energy Technology Data Exchange (ETDEWEB)

    J. King

    2004-03-31

    The primary purpose of this analysis is to evaluate seismic- and igneous-related features, events, and processes (FEPs). These FEPs represent areas of natural system processes that have the potential to produce disruptive events (DE) that could impact repository performance and are related to the geologic processes of tectonism, structural deformation, seismicity, and igneous activity. Collectively, they are referred to as the DE FEPs. This evaluation determines which of the DE FEPs are excluded from modeling used to support the total system performance assessment for license application (TSPA-LA). The evaluation is based on the data and results presented in supporting analysis reports, model reports, technical information, or corroborative documents that are cited in the individual FEP discussions in Section 6.2 of this analysis report.

  14. Features, Events, and Processes: Disruptive Events

    International Nuclear Information System (INIS)

    J. King

    2004-01-01

    The primary purpose of this analysis is to evaluate seismic- and igneous-related features, events, and processes (FEPs). These FEPs represent areas of natural system processes that have the potential to produce disruptive events (DE) that could impact repository performance and are related to the geologic processes of tectonism, structural deformation, seismicity, and igneous activity. Collectively, they are referred to as the DE FEPs. This evaluation determines which of the DE FEPs are excluded from modeling used to support the total system performance assessment for license application (TSPA-LA). The evaluation is based on the data and results presented in supporting analysis reports, model reports, technical information, or corroborative documents that are cited in the individual FEP discussions in Section 6.2 of this analysis report

  15. Modeling time-to-event (survival) data using classification tree analysis.

    Science.gov (United States)

    Linden, Ariel; Yarnold, Paul R

    2017-12-01

    Time to the occurrence of an event is often studied in health research. Survival analysis differs from other designs in that follow-up times for individuals who do not experience the event by the end of the study (called censored) are accounted for in the analysis. Cox regression is the standard method for analysing censored data, but the assumptions required of these models are easily violated. In this paper, we introduce classification tree analysis (CTA) as a flexible alternative for modelling censored data. Classification tree analysis is a "decision-tree"-like classification model that provides parsimonious, transparent (ie, easy to visually display and interpret) decision rules that maximize predictive accuracy, derives exact P values via permutation tests, and evaluates model cross-generalizability. Using empirical data, we identify all statistically valid, reproducible, longitudinally consistent, and cross-generalizable CTA survival models and then compare their predictive accuracy to estimates derived via Cox regression and an unadjusted naïve model. Model performance is assessed using integrated Brier scores and a comparison between estimated survival curves. The Cox regression model best predicts average incidence of the outcome over time, whereas CTA survival models best predict either relatively high, or low, incidence of the outcome over time. Classification tree analysis survival models offer many advantages over Cox regression, such as explicit maximization of predictive accuracy, parsimony, statistical robustness, and transparency. Therefore, researchers interested in accurate prognoses and clear decision rules should consider developing models using the CTA-survival framework. © 2017 John Wiley & Sons, Ltd.

  16. Risk analysis of brachytherapy events

    International Nuclear Information System (INIS)

    Buricova, P.; Zackova, H.; Hobzova, L.; Novotny, J.; Kindlova, A.

    2005-01-01

    For prevention radiological events it is necessary to identify hazardous situation and to analyse the nature of committed errors. Though the recommendation on the classification and prevention of radiological events: Radiological accidents has been prepared in the framework of Czech Society of Radiation Oncology, Biology and Physics and it was approved by Czech regulatory body (SONS) in 1999, only a few reports have been submitted up to now from brachytherapy practice. At the radiotherapy departments attention has been paid more likely to the problems of dominant teletherapy treatments. But in the two last decades the usage of brachytherapy methods has gradually increased because .nature of this treatment well as the possibilities of operating facility have been completely changed: new radionuclides of high activity are introduced and sophisticate afterloading systems controlled by computers are used. Consequently also the nature of errors, which can occurred in the clinical practice, has been changing. To determine the potentially hazardous parts of procedure the so-called 'process tree', which follows the flow of entire treatment process, has been created for most frequent type of applications. Marking the location of errors on the process tree indicates where failures occurred and accumulation of marks along branches show weak points in the process. Analysed data provide useful information to prevent medical events in brachytherapy .The results strength the requirements given in Recommendations of SONS and revealed the need for its amendment. They call especially for systematic registration of the events. (authors)

  17. Simplified containment event tree analysis for the Sequoyah Ice Condenser containment

    International Nuclear Information System (INIS)

    Galyean, W.J.; Schroeder, J.A.; Pafford, D.J.

    1990-12-01

    An evaluation of a Pressurized Water Reactor (PER) ice condenser containment was performed. In this evaluation, simplified containment event trees (SCETs) were developed that utilized the vast storehouse of information generated by the NRC's Draft NUREG-1150 effort. Specifically, the computer programs and data files produced by the NUREG-1150 analysis of Sequoyah were used to electronically generate SCETs, as opposed to the NUREG-1150 accident progression event trees (APETs). This simplification was performed to allow graphic depiction of the SCETs in typical event tree format, which facilitates their understanding and use. SCETs were developed for five of the seven plant damage state groups (PDSGs) identified by the NUREG-1150 analyses, which includes: both short- and long-term station blackout sequences (SBOs), transients, loss-of-coolant accidents (LOCAs), and anticipated transient without scram (ATWS). Steam generator tube rupture (SGTR) and event-V PDSGs were not analyzed because of their containment bypass nature. After being benchmarked with the APETs, in terms of containment failure mode and risk, the SCETs were used to evaluate a number of potential containment modifications. The modifications were examined for their potential to mitigate or prevent containment failure from hydrogen burns or direct impingement on the containment by the core, (both factors identified as significant contributors to risk in the NUREG-1150 Sequoyah analysis). However, because of the relatively low baseline risk postulated for Sequoyah (i.e., 12 person-rems per reactor year), none of the potential modifications appear to be cost effective. 15 refs., 10 figs. , 17 tabs

  18. Analysis of mutations in the human HPRT gene induced by accelerated heavy-ion irradiation

    International Nuclear Information System (INIS)

    Kagawa, Yasuhiro; Yatagai, Fumio; Hanaoka, Fumio; Suzuki, Masao; Kase, Youko; Kobayashi, Akiko; Hirano, Masahiko; Kato, Takesi; Watanabe, Masami.

    1995-01-01

    Multiplex PCR analysis of HPRT(-) mutations in human embryo (HE) cells induced by 230 keV/μm carbon-ion irradiation showed no large deletion around the exon regions of the locus gene in contrast to the irradiations at different LETs. To identify these mutations, the sequence alterations in a cDNA of hprt gene were determined for 18 mutant clones in this study. Missing of exon 6 was the most frequent mutational event (10 clones), and missing of both exons 6 and 8 was next most frequent event (6 clones), then base substitutions (2 clones). These characteristics were not seen in a similar analysis of spontaneous mutations, which showed base substitution (5 clones), frameshift (2 clones), missing of both exons 2 and 3 (2 clones), and a single unidentified clone. Direct sequencing and restriction enzyme digestion of the genomic DNA of the mutants which showed missing of exons 6 and 8 in the cDNA, supports the possibility that they were induced by aberrant mRNA splicing. (author)

  19. Human-centered modeling in human reliability analysis: some trends based on case studies

    International Nuclear Information System (INIS)

    Mosneron-Dupin, F.; Reer, B.; Heslinga, G.; Straeter, O.; Gerdes, V.; Saliou, G.; Ullwer, W.

    1997-01-01

    As an informal working group of researchers from France, Germany and The Netherlands created in 1993, the EARTH association is investigating significant subjects in the field of human reliability analysis (HRA). Our initial review of cases from nuclear operating experience showed that decision-based unrequired actions (DUA) contribute to risk significantly on the one hand. On the other hand, our evaluation of current HRA methods showed that these methods do not cover such actions adequately. Especially, practice-oriented guidelines for their predictive identification are lacking. We assumed that a basic cause for such difficulties was that these methods actually use a limited representation of the stimulus-organism-response (SOR) paradigm. We proposed a human-centered model, which better highlights the active role of the operators and the importance of their culture, attitudes and goals. This orientation was encouraged by our review of current HRA research activities. We therefore decided to envisage progress by identifying cognitive tendencies in the context of operating and simulator experience. For this purpose, advanced approaches for retrospective event analysis were discussed. Some orientations for improvements were proposed. By analyzing cases, various cognitive tendencies were identified, together with useful information about their context. Some of them match psychological findings already published in the literature, some of them are not covered adequately by the literature that we reviewed. Finally, this exploratory study shows that contextual and case-illustrated findings about cognitive tendencies provide useful help for the predictive identification of DUA in HRA. More research should be carried out to complement our findings and elaborate more detailed and systematic guidelines for using them in HRA studies

  20. Neural network approach in multichannel auditory event-related potential analysis.

    Science.gov (United States)

    Wu, F Y; Slater, J D; Ramsay, R E

    1994-04-01

    Even though there are presently no clearly defined criteria for the assessment of P300 event-related potential (ERP) abnormality, it is strongly indicated through statistical analysis that such criteria exist for classifying control subjects and patients with diseases resulting in neuropsychological impairment such as multiple sclerosis (MS). We have demonstrated the feasibility of artificial neural network (ANN) methods in classifying ERP waveforms measured at a single channel (Cz) from control subjects and MS patients. In this paper, we report the results of multichannel ERP analysis and a modified network analysis methodology to enhance automation of the classification rule extraction process. The proposed methodology significantly reduces the work of statistical analysis. It also helps to standardize the criteria of P300 ERP assessment and facilitate the computer-aided analysis on neuropsychological functions.

  1. Metagenomic Analysis of Airborne Bacterial Community and Diversity in Seoul, Korea, during December 2014, Asian Dust Event.

    Science.gov (United States)

    Cha, Seho; Srinivasan, Sathiyaraj; Jang, Jun Hyeong; Lee, Dongwook; Lim, Sora; Kim, Kyung Sang; Jheong, Weonhwa; Lee, Dong-Won; Park, Eung-Roh; Chung, Hyun-Mi; Choe, Joonho; Kim, Myung Kyum; Seo, Taegun

    2017-01-01

    Asian dust or yellow sand events in East Asia are a major issue of environmental contamination and human health, causing increasing concern. A high amount of dust particles, especially called as particulate matter 10 (PM10), is transported by the wind from the arid and semi-arid tracks to the Korean peninsula, bringing a bacterial population that alters the terrestrial and atmospheric microbial communities. In this study, we aimed to explore the bacterial populations of Asian dust samples collected during November-December 2014. The dust samples were collected using the impinger method, and the hypervariable regions of the 16S rRNA gene were amplified using PCR followed by pyrosequencing. Analysis of the sequencing data were performed using Mothur software. The data showed that the number of operational taxonomic units and diversity index during Asian dust events were higher than those during non-Asian dust events. At the phylum level, the proportions of Proteobacteria, Actinobacteria, and Firmicutes were different between Asian dust and non-Asian dust samples. At the genus level, the proportions of the genus Bacillus (6.9%), Arthrobacter (3.6%), Blastocatella (2%), Planomicrobium (1.4%) were increased during Asian dust compared to those in non-Asian dust samples. This study showed that the significant relationship between bacterial populations of Asian dust samples and non-Asian dust samples in Korea, which could significantly affect the microbial population in the environment.

  2. Analysis of transverse momentum and event shape in νN scattering

    International Nuclear Information System (INIS)

    Bosetti, P.C.; Graessler, H.; Lanske, D.; Schulte, R.; Schultze, K.; Simopoulou, E.; Vayaki, A.; Barnham, K.W.J.; Hamisi, F.; Miller, D.B.; Mobayyen, M.M.; Wainstein, S.; Aderholz, M.; Hantke, D.; Hoffmann, E.; Katz, U.F.; Kern, J.; Schmitz, N.; Wittek, W.; Albajar, C.; Batley, J.R.; Myatt, G.; Perkins, D.H.; Radojicic, D.; Renton, P.; Saitta, S.; Bullock, F.W.; Burke, S.

    1990-01-01

    The transverse momentum distributions of hadrons produced in neutrino-nucleon charged current interactions and their dependence on W are analysed in detail. It is found that the components of the transverse momentum in the event plane and normal to it increase with W at about the same rate throughout the available W range. A comparison with e + e - data is made. Studies of the energy flow and angular distributions in the events classified as planar do not show clear evidence for high energy, wide angle gluon radiation, in contrast to the conclusion of a previous analysis of similar neutrino data. (orig.)

  3. Behaviorism, private events, and the molar view of behavior.

    Science.gov (United States)

    Baum, William M

    2011-01-01

    Viewing the science of behavior (behavior analysis) to be a natural science, radical behaviorism rejects any form of dualism, including subjective-objective or inner-outer dualism. Yet radical behaviorists often claim that treating private events as covert behavior and internal stimuli is necessary and important to behavior analysis. To the contrary, this paper argues that, compared with the rejection of dualism, private events constitute a trivial idea and are irrelevant to accounts of behavior. Viewed in the framework of evolutionary theory or for any practical purpose, behavior is commerce with the environment. By its very nature, behavior is extended in time. The temptation to posit private events arises when an activity is viewed in too small a time frame, obscuring what the activity does. When activities are viewed in an appropriately extended time frame, private events become irrelevant to the account. This insight provides the answer to many philosophical questions about thinking, sensing, and feeling. Confusion about private events arises in large part from failure to appreciate fully the radical implications of replacing mentalistic ideas about language with the concept of verbal behavior. Like other operant behavior, verbal behavior involves no agent and no hidden causes; like all natural events, it is caused by other natural events. In a science of behavior grounded in evolutionary theory, the same set of principles applies to verbal and nonverbal behavior and to human and nonhuman organisms.

  4. Behaviorism, Private Events, and the Molar View of Behavior

    Science.gov (United States)

    Baum, William M

    2011-01-01

    Viewing the science of behavior (behavior analysis) to be a natural science, radical behaviorism rejects any form of dualism, including subjective–objective or inner–outer dualism. Yet radical behaviorists often claim that treating private events as covert behavior and internal stimuli is necessary and important to behavior analysis. To the contrary, this paper argues that, compared with the rejection of dualism, private events constitute a trivial idea and are irrelevant to accounts of behavior. Viewed in the framework of evolutionary theory or for any practical purpose, behavior is commerce with the environment. By its very nature, behavior is extended in time. The temptation to posit private events arises when an activity is viewed in too small a time frame, obscuring what the activity does. When activities are viewed in an appropriately extended time frame, private events become irrelevant to the account. This insight provides the answer to many philosophical questions about thinking, sensing, and feeling. Confusion about private events arises in large part from failure to appreciate fully the radical implications of replacing mentalistic ideas about language with the concept of verbal behavior. Like other operant behavior, verbal behavior involves no agent and no hidden causes; like all natural events, it is caused by other natural events. In a science of behavior grounded in evolutionary theory, the same set of principles applies to verbal and nonverbal behavior and to human and nonhuman organisms. PMID:22532740

  5. Incident sequence analysis; event trees, methods and graphical symbols

    International Nuclear Information System (INIS)

    1980-11-01

    When analyzing incident sequences, unwanted events resulting from a certain cause are looked for. Graphical symbols and explanations of graphical representations are presented. The method applies to the analysis of incident sequences in all types of facilities. By means of the incident sequence diagram, incident sequences, i.e. the logical and chronological course of repercussions initiated by the failure of a component or by an operating error, can be presented and analyzed simply and clearly

  6. Analysis and Modelling of Taste and Odour Events in a Shallow Subtropical Reservoir

    Directory of Open Access Journals (Sweden)

    Edoardo Bertone

    2016-08-01

    Full Text Available Understanding and predicting Taste and Odour events is as difficult as critical for drinking water treatment plants. Following a number of events in recent years, a comprehensive statistical analysis of data from Lake Tingalpa (Queensland, Australia was conducted. Historical manual sampling data, as well as data remotely collected by a vertical profiler, were collected; regression analysis and self-organising maps were the used to determine correlations between Taste and Odour compounds and potential input variables. Results showed that the predominant Taste and Odour compound was geosmin. Although one of the main predictors was the occurrence of cyanobacteria blooms, it was noticed that the cyanobacteria species was also critical. Additionally, water temperature, reservoir volume and oxidised nitrogen availability, were key inputs determining the occurrence and magnitude of the geosmin peak events. Based on the results of the statistical analysis, a predictive regression model was developed to provide indications on the potential occurrence, and magnitude, of peaks in geosmin concentration. Additionally, it was found that the blue green algae probe of the lake’s vertical profiler has the potential to be used as one of the inputs for an automated geosmin early warning system.

  7. Thousands of exon skipping events differentiate among splicing patterns in sixteen human tissues [v1; ref status: indexed, http://f1000r.es/1p0

    Directory of Open Access Journals (Sweden)

    Liliana Florea

    2013-09-01

    Full Text Available Alternative splicing is widely recognized for its roles in regulating genes and creating gene diversity. However, despite many efforts, the repertoire of gene splicing variation is still incompletely characterized, even in humans. Here we describe a new computational system, ASprofile, and its application to RNA-seq data from Illumina’s Human Body Map project (>2.5 billion reads.  Using the system, we identified putative alternative splicing events in 16 different human tissues, which provide a dynamic picture of splicing variation across the tissues. We detected 26,989 potential exon skipping events representing differences in splicing patterns among the tissues. A large proportion of the events (>60% were novel, involving new exons (~3000, new introns (~16000, or both. When tracing these events across the sixteen tissues, only a small number (4-7% appeared to be differentially expressed (‘switched’ between two tissues, while 30-45% showed little variation, and the remaining 50-65% were not present in one or both tissues compared.  Novel exon skipping events appeared to be slightly less variable than known events, but were more tissue-specific. Our study represents the first effort to build a comprehensive catalog of alternative splicing in normal human tissues from RNA-seq data, while providing insights into the role of alternative splicing in shaping tissue transcriptome differences. The catalog of events and the ASprofile software are freely available from the Zenodo repository (http://zenodo.org/record/7068; doi:10.5281/zenodo.7068 and from our web site http://ccb.jhu.edu/software/ASprofile.

  8. Pleasant and unpleasant odors influence hedonic evaluations of human faces: an event-related potential study.

    Directory of Open Access Journals (Sweden)

    Stephanie Jane Cook

    2015-12-01

    Full Text Available Odors can alter hedonic evaluations of human faces, but the neural mechanisms of such effects are poorly understood. The present study aimed to analyze the neural underpinning of odor-induced changes in evaluations of human faces in an odor-priming paradigm, using event-related potentials (ERPs. Healthy, young participants (N = 20 rated neutral faces presented after a three second pulse of a pleasant odor (jasmine, unpleasant odor (methylmercaptan, or no-odor control (clean air. Neutral faces presented in the pleasant odor condition were rated more pleasant than the same faces presented in the no-odor control condition, which in turn were rated more pleasant than faces in the unpleasant odor condition. Analysis of face-related potentials revealed four clusters of electrodes significantly affected by odor condition at specific time points during long-latency epochs (600−950 ms. In the 620−640 ms interval, two scalp-time clusters showed greater negative potential in the right parietal electrodes in response to faces in the pleasant odor condition, compared to those in the no-odor and unpleasant odor conditions. At 926 ms, face-related potentials showed greater positivity in response to faces in the pleasant and unpleasant odor conditions at the left and right lateral frontal-temporal electrodes, respectively. Our data shows that odor-induced shifts in evaluations of faces were associated with amplitude changes in the late (> 600 and ultra-late (> 900 ms latency epochs. The observed amplitude changes during the ultra-late epoch are consistent with a left/right hemisphere bias towards pleasant/unpleasant odor effects. Odors alter evaluations of human faces, even when there is a temporal lag between presentation of odors and faces. Our results provide an initial understanding of the neural mechanisms underlying effects of odors on hedonic evaluations.

  9. Analysis of external flooding events occurred in foreign nuclear power plant sites

    International Nuclear Information System (INIS)

    Li Dan; Cai Hankun; Xiao Zhi; An Hongzhen; Mao Huan

    2013-01-01

    This paper screens and studies 17 external flooding events occurred in foreign NPP sites, analysis the characteristic of external flooding events based on the source of the flooding, the impact on the building, systems and equipment, as well as the threat to nuclear safety. Furthermore, based on the experiences and lessons learned from Fukushima nuclear accident relating to external flooding and countermeasures carried out in the world, some suggestions are proposed in order to improve external flooding response capacity for Chinese NPPs. (authors)

  10. Human reliability analysis as part of the Probabilistic Safety Assessment - level 1 for the Kozloduy NPP unit 3

    Energy Technology Data Exchange (ETDEWEB)

    Ilieva, M [Risk Engineereing Ltd., Sofia (Bulgaria)

    1996-12-31

    Human errors probabilities have been evaluated using Accident Sequence Evaluation Program (ASEP). The model accounts for dynamic human actions as separate top events in event trees and excludes any `repair` actions and operator actions to backup the failed automatic signals. A small loss of coolant accident (LOCA) is analysed as an example. Full diagram of the event tree and 4 different scenarios of human action are presented. 6 refs., 2 figs., 1 tab.

  11. Human reliability analysis as part of the Probabilistic Safety Assessment - level 1 for the Kozloduy NPP unit 3

    International Nuclear Information System (INIS)

    Ilieva, M.

    1995-01-01

    Human errors probabilities have been evaluated using Accident Sequence Evaluation Program (ASEP). The model accounts for dynamic human actions as separate top events in event trees and excludes any 'repair' actions and operator actions to backup the failed automatic signals. A small loss of coolant accident (LOCA) is analysed as an example. Full diagram of the event tree and 4 different scenarios of human action are presented. 6 refs., 2 figs., 1 tab

  12. RETRIEVAL EVENTS EVALUATION

    International Nuclear Information System (INIS)

    Wilson, T.

    1999-01-01

    The purpose of this analysis is to evaluate impacts to the retrieval concept presented in the Design Analysis ''Retrieval Equipment and Strategy'' (Reference 6), from abnormal events based on Design Basis Events (DBE) and Beyond Design Basis Events (BDBE) as defined in two recent analyses: (1) DBE/Scenario Analysis for Preclosure Repository Subsurface Facilities (Reference 4); and (2) Preliminary Preclosure Design Basis Event Calculations for the Monitored Geologic Repository (Reference 5) The objective of this task is to determine what impacts the DBEs and BDBEs have on the equipment developed for retrieval. The analysis lists potential impacts and recommends changes to be analyzed in subsequent design analyses for developed equipment, or recommend where additional equipment may be needed, to allow retrieval to be performed in all DBE or BDBE situations. This analysis supports License Application design and therefore complies with the requirements of Systems Description Document input criteria comparison as presented in Section 7, Conclusions. In addition, the analysis discusses the impacts associated with not using concrete inverts in the emplacement drifts. The ''Retrieval Equipment and Strategy'' analysis was based on a concrete invert configuration in the emplacement drift. The scope of the analysis, as presented in ''Development Plan for Retrieval Events Evaluation'' (Reference 3) includes evaluation and criteria of the following: Impacts to retrieval from the emplacement drift based on DBE/BDBEs, and changes to the invert configuration for the preclosure period. Impacts to retrieval from the main drifts based on DBE/BDBEs for the preclosure period

  13. Root cause analysis of critical events in neurosurgery, New South Wales.

    Science.gov (United States)

    Perotti, Vanessa; Sheridan, Mark M P

    2015-09-01

    Adverse events reportedly occur in 5% to 10% of health care episodes. Not all adverse events are the result of error; they may arise from systemic faults in the delivery of health care. Catastrophic events are not only physically devastating to patients, but they also attract medical liability and increase health care costs. Root cause analysis (RCA) has become a key tool for health care services to understand those adverse events. This study is a review of all the RCA case reports involving neurosurgical patients in New South Wales between 2008 and 2013. The case reports and data were obtained from the Clinical Excellence Commission database. The data was then categorized by the root causes identified and the recommendations suggested by the RCA committees. Thirty-two case reports were identified in the RCA database. Breaches in policy account for the majority of root causes identified, for example, delays in transfer of patients or wrong-site surgery, which always involved poor adherence to correct patient and site identification procedures. The RCA committees' recommendations included education for staff, and improvements in rostering and procedural guidelines. RCAs have improved the patient safety profile; however, the RCA committees have no power to enforce any recommendation or ensure compliance. A single RCA may provide little learning beyond the unit and staff involved. However, through aggregation of RCA data and dissemination strategies, health care workers can learn from adverse events and prevent future events from occurring. © 2015 Royal Australasian College of Surgeons.

  14. Features, Events, and Processes: Disruptive Events

    International Nuclear Information System (INIS)

    P. Sanchez

    2004-01-01

    The purpose of this analysis report is to evaluate and document the inclusion or exclusion of the disruptive events features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment for license application (TSPA-LA). A screening decision, either ''Included'' or ''Excluded,'' is given for each FEP, along with the technical basis for screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), and (f) [DIRS 156605]. The FEPs addressed in this report deal with both seismic and igneous disruptive events, such as fault displacements through the repository and an igneous intrusion into the repository. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded). Previous versions of this report were developed to support the total system performance assessments (TSPA) for various prior repository designs. This revision addresses the repository design for the license application (LA)

  15. Features, Events, and Processes: Disruptive Events

    Energy Technology Data Exchange (ETDEWEB)

    P. Sanchez

    2004-11-08

    The purpose of this analysis report is to evaluate and document the inclusion or exclusion of the disruptive events features, events, and processes (FEPs) with respect to modeling used to support the total system performance assessment for license application (TSPA-LA). A screening decision, either ''Included'' or ''Excluded,'' is given for each FEP, along with the technical basis for screening decisions. This information is required by the U.S. Nuclear Regulatory Commission (NRC) at 10 CFR 63.114 (d), (e), and (f) [DIRS 156605]. The FEPs addressed in this report deal with both seismic and igneous disruptive events, such as fault displacements through the repository and an igneous intrusion into the repository. For included FEPs, this analysis summarizes the implementation of the FEP in TSPA-LA (i.e., how the FEP is included). For excluded FEPs, this analysis provides the technical basis for exclusion from TSPA-LA (i.e., why the FEP is excluded). Previous versions of this report were developed to support the total system performance assessments (TSPA) for various prior repository designs. This revision addresses the repository design for the license application (LA).

  16. A multiprocessor system for the analysis of pictures of nuclear events

    CERN Document Server

    Bacilieri, P; Matteuzzi, P; Sini, G P; Zanotti, U

    1979-01-01

    The pictures of nuclear events obtained from the bubble chambers such as Gargamelle and BEBC at CERN and others from Serpukhov are geometrically processed at CNAF (Centro Nazionale Analysis Photogrammi) in Bologna. The analysis system includes an Erasme table and a CRT flying spot digitizer. The difficulties connected with the pictures of the four stereoscopic views of the bubble chambers are overcome by the choice of a strong interactive system. (0 refs).

  17. Modeling the recurrent failure to thrive in less than two-year children: recurrent events survival analysis.

    Science.gov (United States)

    Saki Malehi, Amal; Hajizadeh, Ebrahim; Ahmadi, Kambiz; Kholdi, Nahid

    2014-01-01

    This study aimes to evaluate the failure to thrive (FTT) recurrent event over time. This longitudinal study was conducted during February 2007 to July 2009. The primary outcome was growth failure. The analysis was done using 1283 children who had experienced FTT several times, based on recurrent events analysis. Fifty-nine percent of the children had experienced the FTT at least one time and 5.3% of them had experienced it up to four times. The Prentice-Williams-Peterson (PWP) model revealed significant relationship between diarrhea (HR=1.26), respiratory infections (HR=1.25), urinary tract infections (HR=1.51), discontinuation of breast-feeding (HR=1.96), teething (HR=1.18), initiation age of complementary feeding (HR=1.11) and hazard rate of the first FTT event. Recurrence nature of the FTT is a main problem, which taking it into account increases the accuracy in analysis of FTT event process and can lead to identify different risk factors for each FTT recurrences.

  18. Genetic stratigraphy of key demographic events in Arabia.

    Science.gov (United States)

    Fernandes, Verónica; Triska, Petr; Pereira, Joana B; Alshamali, Farida; Rito, Teresa; Machado, Alison; Fajkošová, Zuzana; Cavadas, Bruno; Černý, Viktor; Soares, Pedro; Richards, Martin B; Pereira, Luísa

    2015-01-01

    At the crossroads between Africa and Eurasia, Arabia is necessarily a melting pot, its peoples enriched by successive gene flow over the generations. Estimating the timing and impact of these multiple migrations are important steps in reconstructing the key demographic events in the human history. However, current methods based on genome-wide information identify admixture events inefficiently, tending to estimate only the more recent ages, as here in the case of admixture events across the Red Sea (~8-37 generations for African input into Arabia, and 30-90 generations for "back-to-Africa" migrations). An mtDNA-based founder analysis, corroborated by detailed analysis of the whole-mtDNA genome, affords an alternative means by which to identify, date and quantify multiple migration events at greater time depths, across the full range of modern human history, albeit for the maternal line of descent only. In Arabia, this approach enables us to infer several major pulses of dispersal between the Near East and Arabia, most likely via the Gulf corridor. Although some relict lineages survive in Arabia from the time of the out-of-Africa dispersal, 60 ka, the major episodes in the peopling of the Peninsula took place from north to south in the Late Glacial and, to a lesser extent, the immediate post-glacial/Neolithic. Exchanges across the Red Sea were mainly due to the Arab slave trade and maritime dominance (from ~2.5 ka to very recent times), but had already begun by the early Holocene, fuelled by the establishment of maritime networks since ~8 ka. The main "back-to-Africa" migrations, again undetected by genome-wide dating analyses, occurred in the Late Glacial period for introductions into eastern Africa, whilst the Neolithic was more significant for migrations towards North Africa.

  19. A Recent Revisit Study on the Human Error Events of Nuclear Facilities in Korea

    International Nuclear Information System (INIS)

    Lee, Y.-H.

    2016-01-01

    After Fukushima accident we have launched two new projects in Korea. One is for the development of the countermeasures for human errors in nuclear facilities, and the other is for the safety culture of nuclear power plant itself. There had happened several succeeding events that turned out to be the typical flags of the human and organizational factor issues for the safety of the other socio-technical systems as well as nuclear power plants in Korea. The second safety culture project was an ambitious development to establish an infra system utilising system dynamics, business process modeling and big-data techniques to provide effective and efficient information basis to various interest parties related to the nuclear power plants. However the project has been drastically cancelled last year without any further discussion on the original issues raised before in Korea. It may come not only from the conflicting perspectives among the different approaches to nuclear safety culture but also from the misunderstandings on the human factors for the nuclear safety.

  20. A Content-Adaptive Analysis and Representation Framework for Audio Event Discovery from "Unscripted" Multimedia

    Science.gov (United States)

    Radhakrishnan, Regunathan; Divakaran, Ajay; Xiong, Ziyou; Otsuka, Isao

    2006-12-01

    We propose a content-adaptive analysis and representation framework to discover events using audio features from "unscripted" multimedia such as sports and surveillance for summarization. The proposed analysis framework performs an inlier/outlier-based temporal segmentation of the content. It is motivated by the observation that "interesting" events in unscripted multimedia occur sparsely in a background of usual or "uninteresting" events. We treat the sequence of low/mid-level features extracted from the audio as a time series and identify subsequences that are outliers. The outlier detection is based on eigenvector analysis of the affinity matrix constructed from statistical models estimated from the subsequences of the time series. We define the confidence measure on each of the detected outliers as the probability that it is an outlier. Then, we establish a relationship between the parameters of the proposed framework and the confidence measure. Furthermore, we use the confidence measure to rank the detected outliers in terms of their departures from the background process. Our experimental results with sequences of low- and mid-level audio features extracted from sports video show that "highlight" events can be extracted effectively as outliers from a background process using the proposed framework. We proceed to show the effectiveness of the proposed framework in bringing out suspicious events from surveillance videos without any a priori knowledge. We show that such temporal segmentation into background and outliers, along with the ranking based on the departure from the background, can be used to generate content summaries of any desired length. Finally, we also show that the proposed framework can be used to systematically select "key audio classes" that are indicative of events of interest in the chosen domain.

  1. Analysis of Human Communication during Assembly Tasks.

    Science.gov (United States)

    1986-06-01

    AD-A7l 43 ANALYSIS OF HUMAN COMMUNICATION DURING ASSEMBLY TASKS in1(U) CRNEGIE-MELLO UNIY PITTSBURGH PA ROBOTICS INST UNCLSSIIEDK S BARBER ET AL...ao I Dur~~~~IngAbcbyTs; 7c .S:in i lSAo .0. Analysis of Human Communication During Assembly Tasks K. Suzanne Barber and Gerald J. Agin CMU-RI-TR-86-1...TYPE or REPORT & PE-Rioo CevCZaz Analysis of Human Communication During Assembly Inlterim Tasks I . PERFORMING 00RG. REPORT NUMBER 1. £UT~oOR~e) IL

  2. Root Cause Analysis Following an Event at a Nuclear Installation: Reference Manual. Companion CD

    International Nuclear Information System (INIS)

    2015-01-01

    Following an event at a nuclear installation, it is important to determine accurately its root causes so that effective corrective actions can be implemented. As stated in IAEA Safety Standards Series No. SF-1, Fundamental Safety Principles: “Processes must be put in place for the feedback and analysis of operating experience”. If this process is completed effectively, the probability of a similar event occurring is significantly reduced. Guidance on how to establish and implement such a process is given in IAEA Safety Standards Series No. NS-G-2.11, A System for the Feedback of Experience from Events in Nuclear Installations. To cater for the diverse nature of operating experience events, several different root cause analysis (RCA) methodologies and techniques have been developed for effective investigation and analysis. An event here is understood as any unanticipated sequence of occurrences that results in, or potentially results in, consequences to plant operation and safety. RCA is not a topic uniquely relevant to event investigators: knowledge of the concepts enhances the learning characteristics of the whole organization. This knowledge also makes a positive contribution to nuclear safety and helps to foster a culture of preventing event occurrence. This publication allows organizations to deepen their knowledge of these methodologies and techniques and also provides new organizations with a broad overview of the RCA process. It is the outcome of a coordinated effort involving the participation of experts from nuclear organizations, the energy industry and research centres in several Member States. This publication also complements IAEA Services Series No. 10, PROSPER Guidelines: Guidelines for Peer Review and for Plant Self- Assessment of Operational Experience Feedback Process, and is intended to form part of a suite of publications developing the principles set forth in these guidelines. In addition to the information and description of RCA

  3. Bisphosphonates and risk of cardiovascular events: a meta-analysis.

    Directory of Open Access Journals (Sweden)

    Dae Hyun Kim

    Full Text Available Some evidence suggests that bisphosphonates may reduce atherosclerosis, while concerns have been raised about atrial fibrillation. We conducted a meta-analysis to determine the effects of bisphosphonates on total adverse cardiovascular (CV events, atrial fibrillation, myocardial infarction (MI, stroke, and CV death in adults with or at risk for low bone mass.A systematic search of MEDLINE and EMBASE through July 2014 identified 58 randomized controlled trials with longer than 6 months in duration that reported CV events. Absolute risks and the Mantel-Haenszel fixed-effects odds ratios (ORs and 95% confidence intervals (CIs of total CV events, atrial fibrillation, MI, stroke, and CV death were estimated. Subgroup analyses by follow-up duration, population characteristics, bisphosphonate types, and route were performed.Absolute risks over 25-36 months in bisphosphonate-treated versus control patients were 6.5% versus 6.2% for total CV events; 1.4% versus 1.5% for atrial fibrillation; 1.0% versus 1.2% for MI; 1.6% versus 1.9% for stroke; and 1.5% versus 1.4% for CV death. Bisphosphonate treatment up to 36 months did not have any significant effects on total CV events (14 trials; ORs [95% CI]: 0.98 [0.84-1.14]; I2 = 0.0%, atrial fibrillation (41 trials; 1.08 [0.92-1.25]; I2 = 0.0%, MI (10 trials; 0.96 [0.69-1.34]; I2 = 0.0%, stroke (10 trials; 0.99 [0.82-1.19]; I2 = 5.8%, and CV death (14 trials; 0.88 [0.72-1.07]; I2 = 0.0% with little between-study heterogeneity. The risk of atrial fibrillation appears to be modestly elevated for zoledronic acid (6 trials; 1.24 [0.96-1.61]; I2 = 0.0%, not for oral bisphosphonates (26 trials; 1.02 [0.83-1.24]; I2 = 0.0%. The CV effects did not vary by subgroups or study quality.Bisphosphonates do not have beneficial or harmful effects on atherosclerotic CV events, but zoledronic acid may modestly increase the risk of atrial fibrillation. Given the large reduction in fractures with bisphosphonates, changes in

  4. Practical guidance for statistical analysis of operational event data

    International Nuclear Information System (INIS)

    Atwood, C.L.

    1995-10-01

    This report presents ways to avoid mistakes that are sometimes made in analysis of operational event data. It then gives guidance on what to do when a model is rejected, a list of standard types of models to consider, and principles for choosing one model over another. For estimating reliability, it gives advice on which failure modes to model, and moment formulas for combinations of failure modes. The issues are illustrated with many examples and case studies

  5. Eradication of hepatitis C virus and non-liver-related non-acquired immune deficiency syndrome-related events in human immunodeficiency virus/hepatitis C virus coinfection.

    Science.gov (United States)

    Berenguer, Juan; Rodríguez-Castellano, Elena; Carrero, Ana; Von Wichmann, Miguel A; Montero, Marta; Galindo, María J; Mallolas, Josep; Crespo, Manuel; Téllez, María J; Quereda, Carmen; Sanz, José; Barros, Carlos; Tural, Cristina; Santos, Ignacio; Pulido, Federico; Guardiola, Josep M; Rubio, Rafael; Ortega, Enrique; Montes, María L; Jusdado, Juan J; Gaspar, Gabriel; Esteban, Herminia; Bellón, José M; González-García, Juan

    2017-08-01

    We assessed non-liver-related non-acquired immunodeficiency syndrome (AIDS)-related (NLR-NAR) events and mortality in a cohort of human immunodeficiency virus (HIV)/hepatitis C virus (HCV)-coinfected patients treated with interferon (IFN) and ribavirin (RBV), between 2000 and 2008. The censoring date was May 31, 2014. Cox regression analysis was performed to assess the adjusted hazard rate (HR) of overall death in responders and nonresponders. Fine and Gray regression analysis was conducted to determine the adjusted subhazard rate (sHR) of NLR deaths and NLR-NAR events considering death as the competing risk. The NLR-NAR events analyzed included diabetes mellitus, chronic renal failure, cardiovascular events, NLR-NAR cancer, bone events, and non-AIDS-related infections. The variables for adjustment were age, sex, past AIDS, HIV transmission category, nadir CD4 + T-cell count, antiretroviral therapy, HIV RNA, liver fibrosis, HCV genotype, and exposure to specific anti-HIV drugs. Of the 1,625 patients included, 592 (36%) had a sustained viral response (SVR). After a median 5-year follow-up, SVR was found to be associated with a significant decrease in the hazard of diabetes mellitus (sHR, 0.57; 95% confidence interval [CI], 0.35-0.93; P = 0.024) and decline in the hazard of chronic renal failure close to the threshold of significance (sHR, 0.43; 95% CI, 0.17-1.09; P = 0.075). Our data suggest that eradication of HCV in coinfected patients is associated not only with a reduction in the frequency of death, HIV progression, and liver-related events, but also with a reduced hazard of diabetes mellitus and possibly of chronic renal failure. These findings argue for the prescription of HCV therapy in coinfected patients regardless of fibrosis stage. (Hepatology 2017;66:344-356). © 2017 The Authors. Hepatology published by Wiley Periodicals, Inc., on behalf of the American Association for the Study of Liver Diseases.

  6. Historical flood data series of Eastern Spanish Coast (14th-20th centuries). Improving identification of climatic patterns and human factors of flood events from primary documentary sources

    Science.gov (United States)

    Alberola, Armando; Barriendos, Mariano; Gil-Guirado, Salvador; Pérez-Morales, Alfredo; Balasch, Carles; Castelltort, Xavier; Mazón, Jordi; Pino, David; Lluís Ruiz-Bellet, Josep; Tuset, Jordi

    2016-04-01

    Historical flood data series of Eastern Spanish Coast (14th-20th centuries). Improving identification of climatic patterns and human factors of flood events from primary documentary sources Armando Alberola, Barriendos, M., Gil-Guirado, S., Pérez Morales, A., Balasch, C., Castelltort, X., Mazón, J., Pino, D., Ruiz-Bellet, J.L., Tuset, J. Historical flood events in eastern spanish coast have been studied by different research groups and projects. Complexity of flood processes, involving atmospheric, surface and human factors, is not easily understandable when long time series are required. Present analysis from PREDIFLOOD Project Consortium defines a new step of flood event databases: Improved access to primary (documentary) and secondary (bibliographical) sources, data collection for all possible locations where floods are detected, and improved system of classification (Barriendos et al., 2014). A first analysis is applied to 8 selected flood series. Long chronologies from PREDIFLOOD Project for Catalonia region (Girona, Barcelona, Tarragona, Lleida, Tortosa). In addition, to cover all sector of spanish mediterranean coast, we introduce Valencia city in Turia River basin. South Eastern sector is cover with Murcia and Caravaca cities, Segura River basin. Extension of area under study required contributions of research teams experienced in work of documentary primary sources (Alberola, 2006; Gil-Guirado, 2013). Flood frequency analysis for long scale periods show natural climatic oscillations into so-called Little Ice Age. There are general patterns, affecting most of basins, but also some local anomalies or singularities. To explain these differences and analogies it is not enough to use purely climatic factors. In this way, we analyze human factors that have been able to influence the variability of floods along last 6 centuries (demography, hydraulic infrastructures, urban development...). This approach improves strongly understanding of mechanisms producing

  7. Using Web Crawler Technology for Geo-Events Analysis: A Case Study of the Huangyan Island Incident

    Directory of Open Access Journals (Sweden)

    Hao Hu

    2014-04-01

    Full Text Available Social networking and network socialization provide abundant text information and social relationships into our daily lives. Making full use of these data in the big data era is of great significance for us to better understand the changing world and the information-based society. Though politics have been integrally involved in the hyperlinked world issues since the 1990s, the text analysis and data visualization of geo-events faced the bottleneck of traditional manual analysis. Though automatic assembly of different geospatial web and distributed geospatial information systems utilizing service chaining have been explored and built recently, the data mining and information collection are not comprehensive enough because of the sensibility, complexity, relativity, timeliness, and unexpected characteristics of political events. Based on the framework of Heritrix and the analysis of web-based text, word frequency, sentiment tendency, and dissemination path of the Huangyan Island incident were studied by using web crawler technology and the text analysis. The results indicate that tag cloud, frequency map, attitudes pie, individual mention ratios, and dissemination flow graph, based on the crawled information and data processing not only highlight the characteristics of geo-event itself, but also implicate many interesting phenomenon and deep-seated problems behind it, such as related topics, theme vocabularies, subject contents, hot countries, event bodies, opinion leaders, high-frequency vocabularies, information sources, semantic structure, propagation paths, distribution of different attitudes, and regional difference of net citizens’ response in the Huangyan Island incident. Furthermore, the text analysis of network information with the help of focused web crawler is able to express the time-space relationship of crawled information and the information characteristic of semantic network to the geo-events. Therefore, it is a useful tool to

  8. Episodes, events, and models

    Directory of Open Access Journals (Sweden)

    Sangeet eKhemlani

    2015-10-01

    Full Text Available We describe a novel computational theory of how individuals segment perceptual information into representations of events. The theory is inspired by recent findings in the cognitive science and cognitive neuroscience of event segmentation. In line with recent theories, it holds that online event segmentation is automatic, and that event segmentation yields mental simulations of events. But it posits two novel principles as well: first, discrete episodic markers track perceptual and conceptual changes, and can be retrieved to construct event models. Second, the process of retrieving and reconstructing those episodic markers is constrained and prioritized. We describe a computational implementation of the theory, as well as a robotic extension of the theory that demonstrates the processes of online event segmentation and event model construction. The theory is the first unified computational account of event segmentation and temporal inference. We conclude by demonstrating now neuroimaging data can constrain and inspire the construction of process-level theories of human reasoning.

  9. The Run 2 ATLAS Analysis Event Data Model

    CERN Document Server

    SNYDER, S; The ATLAS collaboration; NOWAK, M; EIFERT, T; BUCKLEY, A; ELSING, M; GILLBERG, D; MOYSE, E; KOENEKE, K; KRASZNAHORKAY, A

    2014-01-01

    During the LHC's first Long Shutdown (LS1) ATLAS set out to establish a new analysis model, based on the experience gained during Run 1. A key component of this is a new Event Data Model (EDM), called the xAOD. This format, which is now in production, provides the following features: A separation of the EDM into interface classes that the user code directly interacts with, and data storage classes that hold the payload data. The user sees an Array of Structs (AoS) interface, while the data is stored in a Struct of Arrays (SoA) format in memory, thus making it possible to efficiently auto-vectorise reconstruction code. A simple way of augmenting and reducing the information saved for different data objects. This makes it possible to easily decorate objects with new properties during data analysis, and to remove properties that the analysis does not need. A persistent file format that can be explored directly with ROOT, either with or without loading any additional libraries. This allows fast interactive naviga...

  10. Results of the event sequence reliability benchmark exercise

    International Nuclear Information System (INIS)

    Silvestri, E.

    1990-01-01

    The Event Sequence Reliability Benchmark Exercise is the fourth of a series of benchmark exercises on reliability and risk assessment, with specific reference to nuclear power plant applications, and is the logical continuation of the previous benchmark exercises on System Analysis Common Cause Failure and Human Factors. The reference plant is the Nuclear Power Plant at Grohnde Federal Republic of Germany a 1300 MW PWR plant of KWU design. The specific objective of the Exercise is to model, to quantify and to analyze such event sequences initiated by the occurrence of a loss of offsite power that involve the steam generator feed. The general aim is to develop a segment of a risk assessment, which ought to include all the specific aspects and models of quantification, such as common canal failure, Human Factors and System Analysis, developed in the previous reliability benchmark exercises, with the addition of the specific topics of dependences between homologous components belonging to different systems featuring in a given event sequence and of uncertainty quantification, to end up with an overall assessment of: - the state of the art in risk assessment and the relative influences of quantification problems in a general risk assessment framework. The Exercise has been carried out in two phases, both requiring modelling and quantification, with the second phase adopting more restrictive rules and fixing certain common data, as emerged necessary from the first phase. Fourteen teams have participated in the Exercise mostly from EEC countries, with one from Sweden and one from the USA. (author)

  11. The analysis of competing events like cause-specific mortality--beware of the Kaplan-Meier method

    NARCIS (Netherlands)

    Verduijn, Marion; Grootendorst, Diana C.; Dekker, Friedo W.; Jager, Kitty J.; le Cessie, Saskia

    2011-01-01

    Kaplan-Meier analysis is a popular method used for analysing time-to-event data. In case of competing event analyses such as that of cardiovascular and non-cardiovascular mortality, however, the Kaplan-Meier method profoundly overestimates the cumulative mortality probabilities for each of the

  12. Domain-restricted mutation analysis to identify novel driver events in human cancer

    Directory of Open Access Journals (Sweden)

    Sanket Desai

    2017-10-01

    Full Text Available Analysis of mutational spectra across various cancer types has given valuable insights into tumorigenesis. Different approaches have been used to identify novel drivers from the set of somatic mutations, including the methods which use sequence conservation, geometric localization and pathway information. Recent computational methods suggest use of protein domain information for analysis and understanding of the functional consequence of non-synonymous mutations. Similarly, evidence suggests recurrence at specific position in proteins is robust indicators of its functional impact. Building on this, we performed a systematic analysis of TCGA exome derived somatic mutations across 6089 PFAM domains and significantly mutated domains were identified using randomization approach. Multiple alignment of individual domain allowed us to prioritize for conserved residues mutated at analogous positions across different proteins in a statistically disciplined manner. In addition to the known frequently mutated genes, this analysis independently identifies low frequency Meprin and TRAF-Homology (MATH domain in Speckle Type BTB/POZ (SPOP protein, in prostate adenocarcinoma. Results from this analysis will help generate hypotheses about the downstream molecular mechanism resulting in cancer phenotypes.

  13. Human factor reliability program

    International Nuclear Information System (INIS)

    Knoblochova, L.

    2017-01-01

    The human factor's reliability program was at Slovenske elektrarne, a.s. (SE) nuclear power plants. introduced as one of the components Initiatives of Excellent Performance in 2011. The initiative's goal was to increase the reliability of both people and facilities, in response to 3 major areas of improvement - Need for improvement of the results, Troubleshooting support, Supporting the achievement of the company's goals. The human agent's reliability program is in practice included: - Tools to prevent human error; - Managerial observation and coaching; - Human factor analysis; -Quick information about the event with a human agent; -Human reliability timeline and performance indicators; - Basic, periodic and extraordinary training in human factor reliability(authors)

  14. An Estimation of Human Error Probability of Filtered Containment Venting System Using Dynamic HRA Method

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Seunghyun; Jae, Moosung [Hanyang University, Seoul (Korea, Republic of)

    2016-10-15

    The human failure events (HFEs) are considered in the development of system fault trees as well as accident sequence event trees in part of Probabilistic Safety Assessment (PSA). As a method for analyzing the human error, several methods, such as Technique for Human Error Rate Prediction (THERP), Human Cognitive Reliability (HCR), and Standardized Plant Analysis Risk-Human Reliability Analysis (SPAR-H) are used and new methods for human reliability analysis (HRA) are under developing at this time. This paper presents a dynamic HRA method for assessing the human failure events and estimation of human error probability for filtered containment venting system (FCVS) is performed. The action associated with implementation of the containment venting during a station blackout sequence is used as an example. In this report, dynamic HRA method was used to analyze FCVS-related operator action. The distributions of the required time and the available time were developed by MAAP code and LHS sampling. Though the numerical calculations given here are only for illustrative purpose, the dynamic HRA method can be useful tools to estimate the human error estimation and it can be applied to any kind of the operator actions, including the severe accident management strategy.

  15. Using Complex Event Processing (CEP) and vocal synthesis techniques to improve comprehension of sonified human-centric data

    Science.gov (United States)

    Rimland, Jeff; Ballora, Mark

    2014-05-01

    The field of sonification, which uses auditory presentation of data to replace or augment visualization techniques, is gaining popularity and acceptance for analysis of "big data" and for assisting analysts who are unable to utilize traditional visual approaches due to either: 1) visual overload caused by existing displays; 2) concurrent need to perform critical visually intensive tasks (e.g. operating a vehicle or performing a medical procedure); or 3) visual impairment due to either temporary environmental factors (e.g. dense smoke) or biological causes. Sonification tools typically map data values to sound attributes such as pitch, volume, and localization to enable them to be interpreted via human listening. In more complex problems, the challenge is in creating multi-dimensional sonifications that are both compelling and listenable, and that have enough discrete features that can be modulated in ways that allow meaningful discrimination by a listener. We propose a solution to this problem that incorporates Complex Event Processing (CEP) with speech synthesis. Some of the more promising sonifications to date use speech synthesis, which is an "instrument" that is amenable to extended listening, and can also provide a great deal of subtle nuance. These vocal nuances, which can represent a nearly limitless number of expressive meanings (via a combination of pitch, inflection, volume, and other acoustic factors), are the basis of our daily communications, and thus have the potential to engage the innate human understanding of these sounds. Additionally, recent advances in CEP have facilitated the extraction of multi-level hierarchies of information, which is necessary to bridge the gap between raw data and this type of vocal synthesis. We therefore propose that CEP-enabled sonifications based on the sound of human utterances could be considered the next logical step in human-centric "big data" compression and transmission.

  16. T-pattern analysis for the study of temporal structure of animal and human behavior: a comprehensive review.

    Science.gov (United States)

    Casarrubea, M; Jonsson, G K; Faulisi, F; Sorbera, F; Di Giovanni, G; Benigno, A; Crescimanno, G; Magnusson, M S

    2015-01-15

    A basic tenet in the realm of modern behavioral sciences is that behavior consists of patterns in time. For this reason, investigations of behavior deal with sequences that are not easily perceivable by the unaided observer. This problem calls for improved means of detection, data handling and analysis. This review focuses on the analysis of the temporal structure of behavior carried out by means of a multivariate approach known as T-pattern analysis. Using this technique, recurring sequences of behavioral events, usually hard to detect, can be unveiled and carefully described. T-pattern analysis has been successfully applied in the study of various aspects of human or animal behavior such as behavioral modifications in neuro-psychiatric diseases, route-tracing stereotypy in mice, interaction between human subjects and animal or artificial agents, hormonal-behavioral interactions, patterns of behavior associated with emesis and, in our laboratories, exploration and anxiety-related behaviors in rodents. After describing the theory and concepts of T-pattern analysis, this review will focus on the application of the analysis to the study of the temporal characteristics of behavior in different species from rodents to human beings. This work could represent a useful background for researchers who intend to employ such a refined multivariate approach to the study of behavior. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Predicting and managing the human element

    International Nuclear Information System (INIS)

    Duffey, Romney B.; Saull, John W.

    2007-01-01

    Humans introduce new technology into homo-technological systems, as new reactors or any new product. The risk of failure is dependent on our experience, either through technical development and design mistakes and errors, or the product does not have a sufficient competitive advantage in the market. We review the learning curves that are now well known and established for both accident event analysis and product price reduction. We present the facts behind the integral contribution of human error to accidents and risk, and provide the theoretical analysis of outcome rates (undesirable event and cost reduction) based on the Learning Hypothesis. The importance of the accumulated experience on the learning rate, and the depth of experience on the distribution of outcomes, is presented. (author)

  18. Superposed epoch analysis of O+ auroral outflow during sawtooth events and substorms

    Science.gov (United States)

    Nowrouzi, N.; Kistler, L. M.; Lund, E. J.; Cai, X.

    2017-12-01

    Sawtooth events are repeated injection of energetic particles at geosynchronous orbit. Studies have shown that 94% of sawtooth events occurred during magnetic storm times. The main factor that causes a sawtooth event is still an open question. Simulations have suggested that heavy ions like O+ may play a role in triggering the injections. One of the sources of the O+ in the Earth's magnetosphere is the nightside aurora. O+ ions coming from the nightside auroral region have direct access to the near-earth magnetotail. A model (Brambles et al. 2013) for interplanetary coronal mass ejection driven sawtooth events found that nightside O+ outflow caused the subsequent teeth of the sawtooth event through a feedback mechanism. This work is a superposed epoch analysis to test whether the observed auroral outflow supports this model. Using FAST spacecraft data from 1997-2007, we examine the auroral O+ outflow as a function of time relative to an injection onset. Then we determine whether the profile of outflow flux of O+ during sawtooth events is different from the outflow observed during isolated substorms. The auroral region boundaries are estimated using the method of (Andersson et al. 2004). Subsequently the O+ outflow flux inside these boundaries are calculated and binned as a function of superposed epoch time for substorms and sawtooth "teeth". In this way, we will determine if sawtooth events do in fact have greater O+ outflow, and if that outflow is predominantly from the nightside, as suggested by the model results.

  19. The development of human factors technologies -The development of human behaviour analysis techniques-

    International Nuclear Information System (INIS)

    Lee, Jung Woon; Lee, Yong Heui; Park, Keun Ok; Chun, Se Woo; Suh, Sang Moon; Park, Jae Chang

    1995-07-01

    In order to contribute to human error reduction through the studies on human-machine interaction in nuclear power plants, this project has objectives to develop SACOM(Simulation Analyzer with a Cognitive Operator Model) and techniques for human error analysis and application. In this year, we studied the followings: 1) Site investigation of operator tasks, 2) Development of operator task micro structure and revision of micro structure, 3) Development of knowledge representation software and SACOM prototype, 4) Development of performance assessment methodologies in task simulation and analysis of the effects of performance shaping factors. 1) Classification of error shaping factors(ESFs) and development of software for ESF evaluation, 2) Analysis of human error occurrences and revision of analysis procedure, 3) Experiment for human error data collection using a compact nuclear simulator, 4) Development of a prototype data base system of the analyzed information on trip cases. 55 figs, 23 tabs, 33 refs. (Author)

  20. Multi-level human motion analysis for surveillance applications

    NARCIS (Netherlands)

    Lao, W.; Han, Jungong; With, de P.H.N.; Rabbani, M.; Stevenson, R.L.

    2009-01-01

    In this paper, we study a flexible framework for semantic analysis of human motion from a monocular surveillance video. Successful trajectory estimation and human-body modeling facilitate the semantic analysis of human activities in video sequences. As a first contribution, we propose a flexible